taxonID	type	description	language	source
0C081779B91B7842C5B84045FC6523E3.taxon	description	Figs. 1, 6 (habitus), 6 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7842C5B84045FC6523E3.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS / Matute, / Tiko Plantation / 5. v. 1949, B. Malkin ” (UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7842C5B84045FC6523E3.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the absence of a distinct pronotal macula, the frons distinctly concave between median area and eye, the widely separated metaventral plaques that are markedly converging anteriorly (ratios P 2 / w / l / s ca. 1 / 1 / 4 / 5), and the aedeagus (Fig. 6). Also refer to the diagnosis of H. camerocorona for comments on the male genitalia.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7842C5B84045FC6523E3.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.20 / 0.50; head width 0.32; pronotum 0.30 / 0.42, PA 0.36, PB 0.37; elytra 0.67 / 0.50. Habitus as illustrated (Fig. 6). Dorsum dark brown to black, frons and pronotal disc darker, light brown clypeus contrasting with black frons, palpi testaceous, tip of last palpomere not darker. Frons distinctly concave between median area and eye. Dorsum of head and pronotum finely sparsely punctulate, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd; clypeus dull, punctures very fine and dense. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral, and posterosubmedial pronotal foveae rather deep Elytra with summit of posterior declivity at or very near posterior 1 / 3, where elytra transversely quite convex; lateral explanate margins narrow; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Abdominal apex with slightly off-center apical notch. Venter: Mentum and postmentum densely finely punctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 4 / 5. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 4 / 1, sides slightly converging toward rather narrow blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques narrow, straight, markedly converging anteriorly, posteriorly separated by ca. 4 x anterior separation, not raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS concave. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7842C5B84045FC6523E3.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7842C5B84045FC6523E3.taxon	etymology	Etymology. Named in reference to the concavities of the frons.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	description	Figs. 1, 7 (habitus), 7 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS. / Mamfe, 7 - 11. i. 1949 / B. Malkin coll. // Rain forest; clear stream / Gravel and sand ” (UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the light brown clypeus contrasting with dark brown frons, the frons shallowly concave between median area and eye, and the male genitalia (Fig. 7). Also refer to the diagnosis of H. camerocorona for comments on the male genitalia.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.22 / 0.54; head width 0.30; pronotum 0.29 / 0.44, PA 0.36, PB 0.39; elytra 0.76 / 0.54. Habitus as illustrated (Fig. 7). Dorsum brown to dark brown, frons and pronotal disc darker, light brown clypeus contrasting with dark brown frons, palpi testaceous, tip of last palpomere not darker. Frons shallowly concave between median area and eye. Dorsum of head and pronotum finely sparsely punctulate, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd; clypeus dull, punctures very fine and dense. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral, and posterosubmedial pronotal foveae moderately deep Elytra with summit of posterior declivity at or very near posterior 1 / 3, where elytra transversely quite convex; lateral explanate margins narrow; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Abdominal apex with slightly off-center apical notch. Venter: Mentum and postmentum moderately finely punctulate, shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 2 / 1, sides parallel or slightly diverging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques narrow, straight, parallel, raised very slightly, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, protibia slightly arcuate, meso- and metatibiae straight. Abdominal apex with off center apical notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91B7843C5B8451DFE4C217E.taxon	etymology	Etymology. Named in reference to the known distribution and the contrasting sizes of the parameres: right very elongate, left just a nub.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	description	Figs. 1, 8 (habitus), 8 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon, Akonolinga, moist secondary forest and plantation, at light, 7. I. 1978, Loc. # 17 // Gardenforhall — Samuelson ” (LUM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the very fine and widely spaced elytral punctures, the comparatively wide lateral explanate margins of the elytra, the pronotal macula, and the aedeagus (Fig. 8).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.26 / 0.56; head width 0.34; pronotum 0.31 / 0.4, PA 0.37, PB 0.38; elytra 0.75 / 0.56. Habitus as illustrated (Fig. 8). Dorsum brown to dark brown or black, frons and diffusely margined pronotal macula darker, frons almost black, contrasting with light brown clypeus, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum sparcely finely punctulate, more sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd or slightly larger; punctures of clypeus obsolete. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae moderately deep, shallowly confluent, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins wide; punctures fine, on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 3 – 4 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely punctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.7 / 4 / 4. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately wide, slightly converging toward one another anteriorly, weakly raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 2 x P 2. Tibiae slender, protibial very slightly arcuate, meso- and metatibiae straight. Abdominal apex symmetrical; last tergite with slightly off-center apical notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91A7840C5B846E1FF5524F7.taxon	etymology	Etymology. Named in reference to the known distribution, and the wide lateral explanate margins of the elytra.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	description	Figs. 1, 9 (habitus), 9 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. S. Mbalmayo, Nyong River, ex. leaves at margin, 22. v. 1982, leg. P. D. Perkins ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the posterosubmedian foveae moderately deep, medially confluent forming U-shaped depression, the metaventral plaques moderately narrow posteriorly, tapering to point anteriorly, and the aedeagus (Fig. 9). Dorsal habitus similar to other species in Aedeagal Group 1; reliable determinations will require examination of the male genitalia.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.35 / 0.60; head width 0.36; pronotum 0.32 / 0.46, PA 0.37, PB 0.41; elytra 0.82 / 0.60. Habitus as illustrated (Fig. 9). Dorsum generally dark brown, except labrum, clypeus and anterolateral angles of pronotum lighter, palpi testaceous, tip of last palpomere not darker. Frons moderately finely and moderately densely punctulate, pronotum moderately coarsely, moderately densely punctate, punctures much larger than those of frons, interstices shining, ca. 1 – 2 xpd. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae deep, posterolateral foveae very shallow, posterosubmedian foveae moderately deep, medially confluent forming U-shaped depression. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures ca. 1 xpd largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or slightly greater, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming moderately strong angle with one another. Venter: Mentum sparsely finely punctulate, shining; postmentum very finely densely micropunctulate, surrounding areas smooth, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow posteriorly, tapering to point anteriorly, slightly converging toward one another anteriorly, weakly raised, located at sides of shallow median depression. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, straight. Abdominal apex asymmetrical, with deep off-center notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197840C5B84069FAF02377.taxon	etymology	Etymology. Named in reference to the known distribution, and to the smile shaped pronotal fovea.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	description	Figs. 1, 10 (habitus), 10 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. S. Mbalmayo, Nyong River, ex. leaves at margin, 22. v. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (4 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the oval body form, the small body size (ca. 1.18 mm), the posterosubmedial foveae moderately deep, confluent medially forming U-shaped impression, and the aedeagus (Fig. 10). Similar in habitus to some other members of Aedeagal Group 1; reliable determinations will require dissection of males.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.18 / 0.56; head width 0.34; pronotum 0.31 / 0.44, PA 0.36, PB 0.39; elytra 0.70 / 0.56. Habitus as illustrated (Fig. 10). Body form quite oval. Dorsum generally brown to dark brown, maxillary palpi, labrum and clypeus testaceous, pronotum with diffusely margined weakly defined macula. Dorsum of head and pronotum moderately coarsely, often very densely punctulate, frons punctures distinctly finer and less dense than pronotal punctures, interstices shining; punctures of frons disc and pronotal disc ca. 2 – 3 xef, interstices ca. 1 xpd or less; punctures of clypeus very fine, very dense, dull. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae deep, posterolateral absent, posterosubmedial foveae moderately deep, confluent medially forming U-shaped impression. Elytra with summit of posterior declivity at about posterior 1 / 3; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect very slightly separately rounded, in posterior aspect margins forming strong angle with one another. Venter: Mentum sparsely finely punctulate, shining; postmentum very finely densely micropunctulate, surrounding areas smooth, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 2 / 3. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow posteriorly, tapering to point anteriorly, slightly converging toward one another anteriorly, weakly raised, located at sides of shallow median depression. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, straight. Abdominal apex asymmetrical, with deep off-center notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9197841C5B844E9FB622113.taxon	etymology	Etymology. Named in reference to the known distribution, and to the oval body form.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	description	Figs. 1, 11 (habitus), 11 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. Prov., 35 km N. Ngaoundere, stream, 1. v. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (3 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the comparatively large body size (ca. 1.49 mm), the deep pronotal impressions, the comparatively wide P 2, the narrow median depression between the metaventral plaques, and the aedeagus (Fig. 11).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.49 / 0.69; head width 0.39; pronotum 0.37 / 0.51, PA 0.41, PB 0.46; elytra 0.93 / 0.69. Habitus as illustrated (Fig. 11). Dorsum brown to dark brown, frons and pronotal macula darker, maxillary palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately finely moderately sparsely punctulate, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd; clypeus dull, punctures very fine and dense. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae deep, confluent with shallow posterolateral; posterosubmedial pronotal foveae moderately deep, markedly punctate. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 1. P 1 laminate; median carina sinuate in profile. P 2 comparatively wide, l / w ca. 2 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow, slightly arcuate, parallel, tapering anteriorly, weakly raised, located at sides of moderately deep, narrow median depression. AIS width at straight posterior margin ca. 1.5 x P 2. Protibia very slender, straight. All tibiae slender, straight. Abdominal apex asymmetrical, with deep off-center notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9187846C5B8464DFA78241F.taxon	etymology	Etymology. Named in reference to the known distribution, and to the dagger-shaped process of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	description	Figs. 3, 12 (habitus), 12 (aedeagus), 40 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. W. Prov., 7 km. E. Bamenda, stream, 30. i. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (5 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the moderately coarsely, very densely punctulate head and pronotum, and the aedeagus (Fig. 12). The dorsal habitus is very similar to that of H. camerocrebrata and H. cameropetila; all three species are in Aedeagal Species Group 2. H. cameroclandestina is larger in body size than H. cameropetila (ca. 1.32 vs. 1.20 mm); also, the P 2 is wider than that of the two compared species. Reliable determinations of all three species will require examination of the male genitalia, which distinctly differ from one another.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.32 / 0.58; head width 0.33; pronotum 0.32 / 0.47, PA 0.38, PB 0.40; elytra 0.79 / 0.58. Habitus as illustrated (Fig. 12). Dorsum dark brown to black, pronotum without macula, maxillary palpi brown. Dorsum of head and pronotum moderately coarsely, very densely punctulate, each puncture with short, distinctive whitish seta, interstices dull; punctures of frons disc and pronotal disc ca. 2 xef, interstices ca. 1 xpd or less; punctures of clypeus fine, dense. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral and posterosubmedial foveae shallow. Elytra with summit of posterior declivity at about midlength; lateral explanate margins narrow to moderately wide; on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with short and fine conspicuous whitish seta. Intervals not raised, width ca. 0.5 – 1 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum very densely very finely punctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow, parallel, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 2 x P 2. All tibiae moderately stout. Protibia very slightly arcuate. Meso- and metatibiae straight. Abdominal apex symmetrical, with very small and shallow apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 40).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7846C5B84399FDA2232F.taxon	etymology	Etymology. Named in reference to the known distribution, and to the close dorsal similarity to H. camerocrebrata n. sp. and H. cameropetila n. sp.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	description	Figs. 3, 13 (habitus), 13 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: Yaounde: Mt. Febe, 950 m., hygropetric, 10. iv. 1982, P. D. Perkins collector ” (MCZ). Paratype: Same data as holotype (1 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the small size (ca. 1.16 mm), the relatively large and wide pronotum (length / width ratio ca. 17 / 25), the moderately deep pronotal foveae, and the aedeagus (Fig. 13).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.16 / 0.54; head width 0.33; pronotum 0.31 / 0.46, PA 0.39, PB 0.41; elytra 0.81 / 0.54. Habitus as illustrated (Fig. 13). Dorsum light brown, head and pronotal macula darker (holotype is teneral), palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum densely moderately finely punctulate, interstices weakly shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 2 xpd; punctures of clypeus very fine and dense. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum relatively large and wide, length / width ratio ca. 17 / 25. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae shallow, posterosubmedial foveae moderately deep. Elytra with posterior declivity very gradual, summit slightly beyond midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum and postmentum finely sparsely punctulate, weakly shining. Genae very slightly raised, shining, with weak posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 2. P 1 laminate; median carina weakly sinuate in profile. P 2 l / w ca. 2 / 1, sides parallel, apex blunt. Plaques moderately narrow, straight, slightly convergent anteriorly, weakly raised, located at sides of moderately deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at straight posterior margin ca. 1.5 x P 2. Pro- meso- and metatibiae moderately stout, straight. Abdominal apex symmetrical, without apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91F7847C5B84451FB28263B.taxon	etymology	Etymology. Named in reference to the known distribution and the very complex aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	description	Figs. 3, 14 (habitus), 14 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: Yaounde: Mt. Febe, 950 m., hygropetric, 10. iv. 1982, P. D. Perkins collector ” (MCZ). Paratypes (120): Same data as holotype (28 MCZ); same data except 7. iv. 1982 (5 MCZ); same data except 18. vi. 1983 (64 MCZ); same data except 14. vi. 1983 (12 MCZ); Yaounde, Mt. Mbankolo, 900 m, hygropetric microhabitat, 20. v. 1982, P. D. Perkins collector (11 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the very densely punctate dorsum, the very narrow P 2 (l / w ca. 4 / 1) and the aedeagus (Fig. 14). Also refer to the diagnosis of H. camerocompressa. Although the aedeagi of H. camerocrebrata and H. cameropetila distinctly differ in several characters, a relationship of the two species is indicated by the shapes of the parameres: large, wide and with similar clusters of setae (Figs. 14, 18).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.33 / 0.57; head width 0.31; pronotum 0.33 / 0.48, PA 0.41, PB 0.42; elytra 0.85 / 0.57. Habitus as illustrated (Fig. 14). Dorsum dark brown to black, pronotum without macula, palpi brown. Dorsum of head and pronotum moderately coarsely, very densely punctulate, each puncture with short, distinctive whitish seta, interstices dull; punctures of frons disc and pronotal disc ca. 2 – 3 xef, interstices ca. 1 xpd or less; punctures of clypeus fine, dense. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral and posterosubmedial foveae moderately deep. Elytra with summit of rather abrupt posterior declivity at about posterior 1 / 3; lateral explanate margins narrow to moderately wide; on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 0.5 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect very slightly separately rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum and postmentum nitid, dull. Genae very slightly raised, very weakly shining, with posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 6 / 6. P 1 laminate; median carina weakly sinuate in profile. P 2 very narrow, l / w ca. 4 / 1, sides parallel, apex blunt. Plaques narrow, straight or very slightly arcuate, slightly convergent anteriorly, weakly raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at arcuate posterior margin ca. 2.5 x P 2. Pro- meso- and metatibiae straight, moderately stout. Abdominal apex symmetrical, without apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91E7844C5B841A5FACF25D6.taxon	etymology	Etymology. Named in reference to the known distribution and to the very densely punctate dorsum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	description	Figs. 3, 15 (habitus), 15 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: 35 km N. Ngaoundere, stream, 1. v. 1982, P. D. Perkins collector ” (MCZ). Paratypes: 12 km. N. Ngaoundere, lake margin, 1. v. 1982, P. D. Perkins collector (2 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the small size (ca. 1.26 mm), the metaventral plaques that are very small, very narrow, subcarinate lines, and the aedeagus (Fig. 15). The dorsal habitus is similar to that of H. cameroconfinis n. sp., but the present species is much smaller (ca. 1.26 vs. 1.66 mm), and has different ventral proportions (P 2 / w / l / s ca. 1 / 0.15 / 0.15 / 2 vs. 1 / 0.25 / 1.5 / 1). The aedeagi of the two species are markedly dissimilar.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.26 / 0.52; head width 0.33; pronotum 0.30 / 0.41, PA 0.33, PB 0.37; elytra 0.76 / 0.52. Habitus as illustrated (Fig. 15). Dorsum brown to light brown, head and pronotal macula dark brown to black, palpi light brown to testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately densely punctulate, more sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of frons disc slightly smaller than 1 xef, on pronotal disc slightly larger than 1 xef, interstices ca. 2 – 3 xpd or slightly larger; punctures of clypeus obsolete. Labrum apicomedially excised. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae moderately deep, posterolateral pronotal foveae very shallow, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins narrow; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect slightly separately rounded, in posterior aspect margins forming very shallow angle with one another. Venter: Mentum and postmentum densely micropunctulate, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.15 / 0.15 / 2. P 1 laminate; median carina weakly sinuate in profile. P 2 l / w ca. 2.5 / 1, sides almost parallel, apex blunt. Plaques very small, very narrow, subcarinate lines, straight, convergent anteriorly, very weakly if at all raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at straight posterior margin ca. 2 x P 2. Pro-, meso- and metatibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7844C5B84309FE6A209E.taxon	etymology	Etymology. Named in reference to the known distribution and the arm-like shape of the gonopore bearing process of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	description	Figs. 3, 16 (habitus), 16 (aedeagus), 40 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. W. Prov., 7 km. E. Bamenda, stream, 30. i. 1982, leg. P. D. Perkins ” (MCZ). Paratype: Same data as holotype (1 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the ovate body form, the transversely convex pronotum, the posterosubmedial foveae shallow, confluent medially forming U-shaped impression, the very narrow P 2, and the aedeagus (Fig. 16). Differentiation from other similarly shaped members of Aedeagal Species Group 2 will require careful examination of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.30 / 0.57; head width 0.34; pronotum 0.31 / 0.49, PA 0.39, PB 0.41; elytra 0.80 / 0.57. Habitus as illustrated (Fig. 16). Body form ovate. Dorsum generally brown to dark brown, maxillary palpi, labrum and clypeus testaceous, pronotum with diffusely margined weakly defined macula. Dorsum of head and pronotum moderately coarsely, moderately densely punctulate, frons punctures distinctly finer and less dense than pronotal punctures, interstices shining; punctures of frons disc and pronotal disc ca. 1 – 2 xef, interstices ca. 1 – 2 xpd; punctures of clypeus fine, moderately dense, interstices shining medially, dull laterally. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum transversely convex, anterior margin weakly emarginate over middle 1 / 2; anterolateral and posterolateral foveae shallow, posterosubmedial foveae shallow, confluent medially forming U-shaped impression, anteromedial fovea moderately deep. Elytra with summit of posterior declivity at about posterior 1 / 3; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum sparsely very finely punctulate, shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 3 / 3. P 1 laminate; median carina sinuate in profile. P 2 very narrow, l / w ca. 4 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques narrow, very slightly arcuate, tapering anteriorly and slightly converging toward one another anteriorly, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 3 x P 2. All tibiae stout. Protibia widened near midlength, very slightly arcuate. Meso- and metatibiae straight. Abdominal apex symmetrical, last tergite rounded, without apicomedian notch, last ventrite emarginate.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 40).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91D7845C5B847C7FEEC263B.taxon	etymology	Etymology. Named in reference to the known distribution, and to the ovate body form and very curvaceous aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	description	Figs. 3, 17 (habitus), 17 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. NW Yaounde, Isali River nr. Nouma, 2. i. 1983, leg. P. D. Perkins ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the small body size (ca. 1.24 mm), the densely coarsely punctate dorsum, the anterolateral and posterolateral foveae deep, shallowly confluent, the posterosubmedian foveae deep, the plaques absent or very small and very faintly indicated by less dense hydrofuge pubescence, located at sides of very shallow median depression, and the aedeagus (Fig. 17). The habitus is quite similar to that of H. camerocrebrata, but that species has well developed metaventral plaques, and a different aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.24 / 0.54; head width 0.31; pronotum 0.31 / 0.44, PA 0.37, PB 0.38; elytra 0.73 / 0.54. Habitus as illustrated (Fig. 17). Dorsum dark brown to black, maxillary palpi brown, tip of last palpomere not darker. Frons densely moderately coarsely, pronotum coarsely densely punctate, punctures much larger than those of frons, interstices shining, ca. 0.5 – 1 xpd. Labrum apicomedially excised, free margins very weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral and posterolateral foveae deep, shallowly confluent; posterosubmedian foveae deep; anteromedian fovea shallow. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures ca. 1 – 2 xpd largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with short and fine seta. Intervals not raised, width ca. 0.5 – 1 xpd, as are interstices between punctures of a row. Apices in dorsal aspect separately rounded, in posterior aspect margins forming moderately strong angle with one another. Venter: Mentum and postmentum sparsely finely punctulate, shining. Genae raised, without posterior ridge. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 4 / 1, sides parallel or slightly diverging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques absent or very small and very faintly indicated by less dense hydrofuge pubescence, located at sides of very shallow median depression. AIS width at straight posterior margin ca. 2.5 x P 2. All tibiae straight, moderately stout. Abdominal apex symmetrical, with very small apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B91C7845C5B841A5FB2022DF.taxon	etymology	Etymology. Named in reference to the known distribution, and to the deep pronotal foveae.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	description	Figs. 3, 18 (habitus), 18 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS. / Mamfe, 7 - 11. i. 1949 / B. Malkin coll. // Rain forest; clear stream / Gravel and sand ” (UKNHM). Paratypes: Same data as holotype (2 UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of absence of metaventral plaques, the very narrow P 2, and the aedeagus (Fig. 18). For characters differentiating the two species refer to the diagnosis of H. camerosetosa. Although H. cameropetila is smaller than H. camerosetosa in body length (ca. 1.20 vs. 1.33 mm), the width of the mesocoxae are the same in the two species, making the ratio of P 2 width / mesocoxa width approximately 0.12 for H. cameropetila and 0.40 H. camerosetosa. Also refer to the diagnoses of H. millenaria and H. camerocrebrata.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.20 / 0.50; head width 0.30; pronotum 0.29 / 0.42, PA 0.32, PB 0.36; elytra 0.74 / 0.50. Habitus as illustrated (Fig. 18). Dorsum dark brown to black, pronotum without macula, palpi brown. Dorsum of head and pronotum moderately coarsely, very densely punctulate, interstices shining; punctures of frons disc and pronotal disc ca. 2 – 3 xef, interstices ca. 1 xpd or less; punctures of clypeus moderately fine, dense. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral and posterosubmedial foveae moderately deep, anteromedian fovea shallow. Elytra with summit of posterior declivity at about posterior 1 / 3; lateral explanate margins wide; on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 0.5 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect very slightly separately rounded, in posterior aspect margins forming weak angle with one another. Venter: Mentum and postmentum densely finely punctulate, dull. Genae raised, dull, without posterior ridge. Metaventral plaques absent. P 1 laminate; median carina sinuate in profile. P 2 very narrow, l / w ca. 4 / 1, sides parallel, blunt apex raised slightly above mesoventral intercoxal process .. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 4 x P 2. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight. Abdominal apex with very small indistinct apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785AC5B842B8FA6121EB.taxon	etymology	Etymology. Named in reference to the distribution and the very narrow mesoventral intercoxal process (P 2).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	description	Figs. 4, 19 (habitus), 19 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. NW Yaounde, Isali River nr. Nouma, 2. i. 1983, leg. P. D. Perkins ” (MCZ). Paratype: Same data as holotype (1 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the anterolateral pronotal foveae large and deep, posterolateral pronotal foveae absent, the brown to dark brown dorsum, and the aedeagus (Fig. 19). Similar in dorsal habitus to H. cameropalmula and H. millenaria; reliable determinations will require examination of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.35 / 0.60; head width 0.36; pronotum 0.33 / 0.48, PA 0.40, PB 0.43; elytra 0.85 / 0.60. Habitus as illustrated (Fig. 19). Dorsum brown to dark brown, frons and diffusely margined pronotal disc darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately sparcely moderately coarsely punctulate, more sparsely punctulate on pronotal disc than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 – 2 xef, interstices ca. 1 – 2 xpd or slightly larger; punctures of clypeus very fine, very dense, dull. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral pronotal foveae large and deep, posterolateral pronotal foveae absent, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins wide; punctures moderately coarse, on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming moderate angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 2.5. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques narrow, short, slightly converging toward one another anteriorly, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.5 x P 2. All tibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B903785BC5B847ACFA7E273F.taxon	etymology	Etymology. Named in reference to the known distribution, and to the strong hook-shaped process of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	description	Figs. 4, 20 (habitus), 20 (aedeagus), 40 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. W. Prov., 7 km. E. Bamenda, stream, 30. i. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (12 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the relatively large body size (ca. 1.60 mm), the broad body form, the antero- and posterolateral pronotal foveae moderately deep, shallowly confluent, the wide lateral explanate margins of the elytra, and the aedeagus (Fig. 20). Somewhat similar to H. camerocontinua in body size and form, but differing therefrom in denser dorsal punctation, ventral morphology, and aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.59 / 0.71; head width 0.40; pronotum 0.40 / 0.55, PA 0.45, PB 0.48; elytra 0.93 / 0.71. Habitus as illustrated (Fig. 20). Dorsum brown to dark brown or black, frons and diffusely margined pronotal disc darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately sparcely moderately coarsely punctulate, more sparsely punctulate on pronotal disc than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 – 2 xef, interstices ca. 2 – 3 xpd or slightly larger; punctures of clypeus very fine. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae moderately deep, shallowly confluent, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins wide; punctures moderately coarse, on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 3 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 2 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques narrow, very slightly arcuate, converging toward one another anteriorly, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.5 x P 2. Protibia slender, very slightly arcuate. Meso- and metatibiae slender, straight. Abdominal apex asymmetrical, with off-center deep notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 40).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B902785BC5B840A1FB5023E3.taxon	etymology	Etymology. Named in reference to the known distribution, and to the compact body form.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	description	Figs. 4, 21 (habitus), 21 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: 35 km N. Ngaoundere, stream, 1. v. 1982, P. D. Perkins collector ” (MCZ). Paratypes: Same data as holotype (6 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the very narrow P 2 (l / w ca. 4 / 1), the unusual ratios of P 2 width and plaque shape (P 2 / w / l / s ca. 1 / 1 / 6 / 5), and the aedeagus (Fig. 21). Although the P 2 is very narrow, as is that of H. camerocrebrata n. sp., the habitus and aedeagi of the two species markedly differ. H. cameropetila (CAM 13) also has a very narrow P 2, but lacks metaventral plaques.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.40 / 0.61; head width 0.33; pronotum 0.33 / 0.48, PA 0.37, PB 0.39; elytra 0.83 / 0.61. Habitus as illustrated (Fig. 21). Dorsum brown to light brown, head and pronotal macula darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately densely punctulate, more sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd or slightly larger; punctures of clypeus obsolete. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae shallow, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins narrow; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum nitid, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 6 / 5. P 1 laminate; median carina weakly sinuate in profile. P 2 narrow, l / w ca. 4 / 1, sides parallel, apex blunt. Plaques narrow, straight, parallel, weakly raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at straight posterior margin ca. 1.5 x P 2. Pro- meso- and metatibiae slender, straight. Abdominal apex with deep asymmetrical slightly off-center notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9027858C5B8451DFF262136.taxon	etymology	Etymology. Named in reference to the known distribution and the very narrow mesoventral intercoxal process (P 2).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	description	Figs. 4, 22 (habitus), 22 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: 35 km N. Ngaoundere, stream, 1. v. 1982, P. D. Perkins collector ” (MCZ). Paratypes: Same data as holotype (122 MCZ); 12 km. N. Ngaoundere, lake margin, 1. v. 1982, leg. P. D. Perkins (1 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the comparatively large size (ca. 1.62 mm vs. 1.10 – 1.55 for other known species), the narrow metaventral plaques, and the aedeagus (Fig. 9). The dorsal habitus is similar to that of H. camerocubita, but H. cameroconfinis is much larger (ca. 1.62 vs. 1.26 mm), and has different ventral proportions (P 2 / w / l / s ca. 1 / 0.25 / 1.5 / 1 vs. 1 / 0.15 / 0.15 / 2). The aedeagi of the two species are markedly dissimilar (Figs. 15, 22).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.62 / 0.68; head width 0.38; pronotum 0.39 / 0.52, PA 0.44, PB 0.45; elytra 0.94 / 0.68. Habitus as illustrated (Fig. 22). Dorsum brown to light brown, head and pronotal macula darker, palpi light brown to testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately densely punctulate, more sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 2 – 3 xpd or slightly larger; punctures of clypeus obsolete. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral, and posterosubmedial foveae very shallow. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins narrow; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum nitid, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.25 / 1.5 / 1. P 1 laminate; median carina weakly sinuate in profile. P 2 l / w ca. 2 / 1, sides parallel, apex blunt. Plaques narrow, straight, slightly converging toward one another anteriorly, weakly raised, located at sides of moderately deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS concave, width at straight posterior margin ca. 1 x P 2. Pro- and mesotibiae slender, straight. Metatibia slender, straight, inner margin with row of short setae. Abdominal apex with deep asymmetrical slightly off-center notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9017859C5B846A9FC6C24D3.taxon	etymology	Etymology. Named in reference to the known distribution, near the northern limit of the Sudano-Guinean zone (zone 2), just south of the very dry Sudano-Sahelian zone (zone 1).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	description	Figs. 4, 23 (habitus), 23 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS. / Mamfe, 7 - 11. i. 1949 / B. Malkin coll. // Rain forest; clear stream / Gravel and sand ” (UKNHM). Paratype: Same data as holotype (1 UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the moderately densely punctate dorsum, the relatively wide mesoventral intercoxal process (P 2, l / w ca. 2 / 1), and the aedeagus (Fig. 23). Hydraena cameropetila is also densely punctate, but much smaller (1.20), and lacks plaques. H. camerocrebrata is also densely punctate, but much smaller (ca. 1.33 vs. 1.50), and the plaques are larger (P 2 / w / l / s ratios ca. 1 / 1 / 6 / 6 vs. 1 / 0.2 / 2 / 2). Also refer to the diagnosis of H. camerocrebrata.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.49 / 0.62; head width 0.36; pronotum 0.37 / 0.50, PA 0.42, PB 0.44; elytra 0.88 / 0.62. Habitus as illustrated (Fig. 23). Dorsum light brown to dark brown, head, pronotal macula and elytra dark brown, pronotum rather widely margined in light brown to testaceous, palpi testaceous, tip of last palpomere not darker. Dorsum of head moderately finely sparsely punctulate, pronotum moderately coarsely, moderately densely punctate, punctures much larger than those of frons, interstices shining, ca. 1 – 2 xpd. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral and posterolateral foveae moderately deep, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity slightly beyond midlength, where elytra transversely quite convex; lateral explanate margins moderately wide; on basal 1 / 3 punctures larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum and postmentum very finely punctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.2 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 relatively wide, l / w ca. 2 / 1, sides parallel or slightly diverging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques very narrow, very indistinct, straight, parallel, not raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 1 x P 2, or slightly narrower than P 2. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight. Abdominal apex with slightly off center shallow notch in tergite, into which minute apical process of ventrite fits.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9007859C5B8400DFEED2207.taxon	etymology	Etymology. Named in reference to the known distribution and the relatively wide mesoventral intercoxal process (P 2).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	description	Figs. 4, 24 (habitus), 24 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS / Matute, / Tiko Plantation / 5. v. 1949, B. Malkin ” (UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the pronotum with a macula, the absence of posterosubmedial pronotal foveae, and the aedeagus (Fig. 24). Reliable determinations to distinguish this species from other similar members in Aedeagal Species Group 3 will require dissection of males.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.33 / 0.58; head width 0.34; pronotum 0.34 / 0.47, PA 0.38, PB 0.38; elytra 0.82 / 0.58. Habitus as illustrated (Fig. 24). Dorsum testaceous to dark brown, head, pronotal macula and elytra dark brown, pronotum rather widely margined in light brown to testaceous, palpi testaceous, tip of last palpomere not darker. Dorsum of head finely sparsely punctulate, pronotum moderately coarsely, densely punctate, punctures much larger than those of frons, interstices shining, ca. 1 – 2 xpd. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae moderately deep, posterolateral foveae very shallow, posterosubmedial foveae absent. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins narrow; on basal 1 / 3 punctures larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum and postmentum finely punctulate, shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 1 / 4 / 4. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques narrow, straight, parallel or nearly so, not raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 2.5 x P 2. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight. Abdominal apex with apicomedian shallow notch in tergite, into which minute apical process of ventrite fits.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785EC5B842B8FAE62198.taxon	etymology	Etymology. Named in reference to the known distribution and the palmate shape of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	description	Figs. 4, 25 (habitus), 25 (aedeagus), 40 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. W. Prov., Bamenda, stream nr. Skyline Hotel, 1. ii. 1982, leg. P. D. Perkins ” (MCZ). Paratype: Same data as holotype (1 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the absence of metaventral plaques, the frons and pronotum finely sparsely punctulate, the punctures of the pronotum very consistent in size throughout, and the aedeagus (Fig. 25). The dorsal punctation is much finer and sparser than that of H. cameropetila and H. camerosetosa, two species which also lack metaventral plaques. All three species are in different Aedeagal Species Groups.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.20 / 0.53; head width 0.33; pronotum 0.31 / 0.44, PA 0.34, PB 0.39; elytra 0.75 / 0.53. Habitus as illustrated (Fig. 25). Dorsum brown to dark brown, head, pronotal fascia and elytra dark brown, pronotum rather widely bordered anteriorly and posteriorly slightly lighter brown, maxillary palpi testaceous, tip of last palpomere not darker. Frons and pronotum finely sparsely punctulate, punctures of pronotum slightly larger than those of frons, very consistent in size throughout, interstices shining, ca. 1 – 3 xpd. Clypeus medially very finely sparsely punctulate, shining; laterally densely micropunctulate, dull. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae deep, posterolateral and posterosubmedian foveae shallow. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals shining, not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, surrounding areas smooth, shining. Genae raised, shining, without posterior ridge. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques absent. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, straight. Abdominal apex slightly asymmetrical, with deep and wide apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 40).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B907785FC5B846C4FDD424AF.taxon	etymology	Etymology. Named in reference to the fact that the author’s goal of describing more than 1000 new species of water beetles is now happily attained.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	description	Figs. 4, 26 (habitus), 26 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: 35 km N. Ngaoundere, stream, 1. v. 1982, P. D. Perkins collector ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the nearly semicordate pronotum, the widely separated and carinate mesoventral plaques, and the aedeagus (Fig. 26). Refer also to the diagnosis of H. camerosemicordata n. sp.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.35 / 0.57; head width 0.33; pronotum 0.35 / 0.44, PA 0.37, PB 0.33; elytra 0.81 / 0.57. Habitus as illustrated (Fig. 26). Pronotum almost semicordiform, anterior margin much wider than posterior margin. Dorsum brown except head and pronotal fascia black, palpi light brown to testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately punctulate, more sparsely punctulate on fascia than on surrounding areas, interstices shining; punctures of frons disc fine and sparse, less than 1 xef; punctures of pronotal disc ca. 2 xef, interstices ca. 1 – 3 xpd or slightly larger; punctures of clypeus fine, moderately dense. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae moderately deep, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures 2 – 3 xpd and deeper than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, very narrow, width ca. 1 / 2 xpd or less, as are interstices between punctures of a row, each puncture with very short and very fine seta. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum densely micropunctulate, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.15 / 0.15 / 2. P 1 laminate; median carina weakly sinuate in profile. P 2 l / w ca. 2.5 / 1, sides almost parallel, apex blunt. Plaques very small, very narrow, carinate lines, straight, convergent anteriorly, very weakly raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at straight posterior margin ca. 2 x P 2. Protibiae slender, very weakly arcuate. Mesotibiae slender, straight. Metatibiae slender, straight, very slightly wider at midlength than apically. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785FC5B84069FB1223BF.taxon	etymology	Etymology. Named in reference to the known distribution and the carinate metaventral plaques.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	description	Figs. 4, 27 (habitus), 27 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: 35 km N. Ngaoundere, stream, 1. v. 1982, P. D. Perkins collector ” (MCZ). Paratypes: Same data as holotype (6 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the chordate and convex pronotum, the very narrow metaventral plaques, and the aedeagus (Fig. 27). Differentiated from H. camerocarinata n. sp., a species which also has a semichordate pronotum, by the more convex and more chordate pronotum, the deeper pronotal foveae, the area between the antero- and posterolateral pronotal foveae more strongly convex, the more acuminate elytra, and the different proportions of the ventral characters (P 2 / w / l / s ca. 1 / 0.2 / 2 / 2 vs. 1 / 0.15 / 0.15 / 2).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.37 / 0.54; head width 0.31; pronotum 0.37 / 0.44, PA 0.35, PB 0.31; elytra 0.81 / 0.54. Habitus as illustrated (Fig. 27). Pronotum semicordiform, anterior margin much wider than posterior margin. Dorsum brown except head and pronotal fascia black, palpi light brown to testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately punctulate, more sparsely punctulate on fascia than on surrounding areas, interstices effacedly microreticulate, weakly shining; punctures of frons disc fine and sparse, 1 xef or less; punctures of pronotal disc ca. 1 – 2 xef, interstices ca. 1 – 3 xpd; punctures of clypeus fine, moderately dense. Labrum apicomedial excision deep and wide, free margins weakly upturned, angulate laterally and medially. Pronotum distinctly convex, especially transversely, anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae deep, posterosubmedial foveae deep, area between antero- and posterolateral foveae distinctly convex. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures 1 – 2 xpd and deeper than largest pronotal punctures, punctures becoming gradually slightly smaller toward posterior. Intervals not raised, width ca. 1 xpd, interstices between punctures of a row ca. 2 – 3 xpd, each puncture with very short and very fine seta. Apices in dorsal aspect conjointly rather sharply rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum densely micropunctulate, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.2 / 2 / 2. P 1 laminate; median carina weakly sinuate in profile. P 2 l / w ca. 2.5 / 1, sides almost parallel, apex blunt. Plaques very small, very narrow, lines, straight, convergent anteriorly, very weakly if at all raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS weakly concave, width at straight posterior margin ca. 2 x P 2. Pro-, meso- and metatibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B906785CC5B84521FB2421A3.taxon	etymology	Etymology. Named in reference to the known distribution and the semi-chordate pronotum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	description	Figs. 5, 28 (habitus), 28 (aedeagus), 39 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. Prov., 22 km. N. Maroua, desert stream, 14. i. 1982, leg. P. D. Perkins ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the brown to dark brown or black dorsum, the deep anterolateral pronotal foveae, and the aedeagus (Fig. 28). Similar in habitus and size to H. camerocontinua, but differing therefrom in denser dorsal punctation, ventral morphology, and aedeagal characters.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.37 / 0.57; head width 0.34; pronotum 0.32 / 0.45, PA 0.38, PB 0.40; elytra 0.80 / 0.57. Habitus as illustrated (Fig. 28). Dorsum brown to dark brown or black, frons and pronotal disc darker, maxillary palpi light brown, tip of last palpomere not darker. Frons finely moderately densely punctulate, ca. 1 xef, interstices ca. 1 – 2 xpd, interstices shining. Pronotum moderately coarsely moderately densely punctate, ca. 2 xpd of frons punctures; interstices ca. 1 xpd or slightly greater, shining. Clypeus medially very finely sparsely punctulate, shining; laterally very finely densely punctulate, dull. Labrum apicomedially excised, free margins not upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral pronotal foveae deep, posterolateral shallow, posterosubmedial moderately deep. Elytra with summit of posterior declivity at or very near posterior 1 / 3; lateral explanate margins narrow; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 2 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques narrow, straight or very slightly arcuate, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.5 x P 2. Protibia very slender, straight. All tibiae slender, straight. Abdominal apex symmetrical, with deep apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 39).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B905785DC5B84715FBD6271B.taxon	etymology	Etymology. Named in reference to the known distribution, and to the arid area.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	description	Figs. 5, 29 (habitus), 29 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS / Matute, / Tiko Plantation / 5. v. 1949, B. Malkin ” (UKNHM). Paratypes: Same data as holotype (48 UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the pronotum color, mostly black, contrasting with light brown to testaceous color narrowly along anterior and posterior margins, the elytral margins in posterior aspect forming very strong angle with one another, and the aedeagus (Fig. 29).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.25 / 0.54; head width 0.33; pronotum 0.30 / 0.43, PA 0.38, PB 0.39; elytra 0.75 / 0.54. Habitus as illustrated (Fig. 29). Dorsum with head and most of pronotum black, pronotum narrowly along anterior and posterior margins light brown to testaceous, palpi testaceous. Frons and clypeus finely, moderately densely punctulate, interstices shining. Pronotum moderately coarsely, densely punctulate, interstices shining; punctures of pronotal disc ca. 2 – 3 xef, interstices ca. 1 xpd or less. Labrum apicomedially excised, free margins rounded, weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral and posterosubmedial foveae moderately deep. Elytra with summit of posterior declivity at about posterior 1 / 3; lateral explanate margins moderately wide; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect slightly separately rounded, in posterior aspect margins forming very strong angle with one another. Venter: Mentum and postmentum moderately finely punctulate, shining. Genae raised, dull, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques moderately narrow, straight, parallel or nearly so, not raised, located at sides of deep median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B904785DC5B84045FAD62353.taxon	etymology	Etymology. Named in reference to the distribution and the relatively large distal lobe of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	description	Figs. 5, 30 (habitus), 30 (aedeagus), 39 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. Prov., 22 km. N. Maroua, desert stream, 14. i. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (9 MCZ); Same locality, 27. v. 1982, leg. P. D. Perkins (5 MCZ)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the rather elongate body form, the very coarse and very dense pronotal and elytral punctures, interstices narrow walls, shining, the narrow, long plaques, located at sides of deep longitudinal groove-like median sulcus, and the aedeagus (Fig. 30).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.48 / 0.60; head width 0.36; pronotum 0.34 / 0.44, PA 0.40, PB 0.42; elytra 0.92 / 0.60. Habitus as illustrated (Fig. 30). Body form elongate. Dorsum generally brown to dark brown, maxillary palpi, testaceous, pronotum with diffusely margined weakly defined dark brown macula. Dorsum of head and pronotum coarsely, very densely punctulate. Frons punctures distinctly smaller and less dense than pronotal punctures, interstices shining; punctures of frons disc and ca. 2 – 3 xef, interstices ca. 1 – 2 xpd. Pronotal punctures very coarse and very dense, interstices narrow walls, shining. Clypeus very finely sparsely punctulate in median 1 / 3, shining; lateral areas densely micropunctulate, dull. Labrum apicomedially excised, free margins rounded, very weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral foveae deep, confluent, posterosubmedial foveae deep, very coarsely punctate. Elytra with summit of posterior declivity at about midlength; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures. Intervals not raised, width ca. 0.5 xpd or less, sometimes narrow walls, as are interstices between punctures of a row. Apices in dorsal aspect jointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum and postmentum rather coarsely densely micropunctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 2.3 / 1.3. P 1 laminate; median carina sinuate in profile. P 2 narrow, l / w ca. 3 / 1, sides slightly converging toward blunt apex raised slightly above mesoventral intercoxal process. Plaques narrow, long compared to P 2, straight, slightly converging toward one another anteriorly, weakly raised, located at sides of deep longitudinal groove-like median sulcus. AIS width at straight posterior margin ca. 2 x P 2. Protibia moderately arcuate, slightly widened on inner margin over distal 1 / 3. Meso- and metatibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 39).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9047852C5B8448DFB2126A6.taxon	etymology	Etymology. Named in reference to the known distribution, and to the cameo-like aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90B7853C5B841D9FE8C2443.taxon	description	Figs. 5, 31 (habitus), 31 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90B7853C5B841D9FE8C2443.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. Prov., 35 km N. Ngaoundere, stream, 1. v. 1982, leg. P. D. Perkins ” (MCZ). Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the relatively wide and short P 2, l / w ca. 1 / 1, sides slightly diverging toward apex, apex very indistinct, fused with and at same level as mesoventral intercoxal process., the anterolateral pronotal foveae moderately deep, posterolateral pronotal foveae very shallow or absent, and the aedeagus (Fig. 31). Somewhat similar in habitus to H. cameroarida, but differing in finer, sparser dorsal punctation, ventral characters, and aedeagal morphology. Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.47 / 0.67; head width 0.39; pronotum 0.37 / 0.52, PA 0.42, PB 0.47; elytra 0.91 / 0.67. Habitus as illustrated (Fig. 31). Dorsum brown to dark brown or black, frons and diffusely margined pronotal macula darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum sparcely moderately finely punctulate, more sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 3 xpd or slightly larger; punctures of clypeus obsolete. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral pronotal foveae moderately deep, posterolateral pronotal foveae very shallow or absent, posterosubmedial foveae very shallow. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins wide; punctures fine, on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 2 – 3 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming very weak angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.3 / 1 / 1.3. P 1 laminate; median carina sinuate in profile. P 2 relatively wide and short, l / w ca. 1 / 1, sides slightly diverging toward apex, apex very indistinct, fused with and at same level as mesoventral intercoxal process. Plaques narrow, slightly converging toward one another anteriorly, very weakly raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.3 x P 2. Protibia slender, arcuate. Meso- and metatibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90B7853C5B841D9FE8C2443.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90B7853C5B841D9FE8C2443.taxon	etymology	Etymology. Named in reference to the known distribution, and to the fused intercoxal processes of the meso- and metaventrites.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	description	Figs. 5, 32 (habitus), 32 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. NW Yaounde, Isali River nr. Nouma, 2. i. 1983, leg. P. D. Perkins ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the large body size (ca. 1.74 mm, largest known in Cameroon), the pronotum with sides markedly arcuate over middle 1 / 3, the oval, transversely quite convex elytra, the very wide P 1 and P 2, the plaques widely separated carinate lines, and the aedeagus (Fig. 32).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.74 / 0.79; head width 0.42; pronotum 0.42 / 0.58, PA 0.47, PB 0.48; elytra 1.05 / 0.79. Habitus as illustrated (Fig. 32). Pronotum with sides markedly arcuate over middle 1 / 3, sides more strongly sinuate posterior to middle than anterior to middle. Frons finely and moderately sparsely punctulate, punctures ca. 1 xef, interstices ca. 1 – 3 xpd, shining. Pronotum coarsely densely punctate in anterior and posterior 1 / 3, interstices ca. 1 xpd, shining; disc convex, very finely very sparsely punctulate, interstices ca. 3 – 6 xpd, shining. Punctures of clypeus very fine, sparse on disc, interstices shining, very dense, dull laterally. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin emarginate over middle 1 / 2; anterolateral pronotal foveae deep; posterolateral and posterosubmedial pronotal foveae very shallow. Elytra oval, transversely quite convex, posterior declivity abrupt, summit of at or very near midlength; lateral explanate margins wide; punctures coarse, on basal 1 / 3 punctures ca. 2 xpd of largest pronotal punctures, each puncture with very short and very fine seta. Intervals not raised, width ca. 2 – 3 xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum finely sparsely punctulate, shining. Postmentum densely micropunctulate, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.2 / 1 / 1. P 1 and P 2 very wide. P 2 l / w ca. 1 / 1, sides parallel, apex blunt. Plaques widely separated carinate lines, located at sides of deep median depression. AIS very wide, width at straight posterior margin ca. 1.2 x P 2. All tibiae slender. Protibia very slightly arcuate. Meso- and metatibiae straight. Abdominal apex asymmetrical, with deep apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7853C5B843BDFB62209F.taxon	etymology	Etymology. Named in reference to the known distribution, and to the convex dorsum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7850C5B847C1FADD263B.taxon	description	Figs. 5, 33 (habitus), 33 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7850C5B847C1FADD263B.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., Etoug Ebe, stream with dead leaves, 22. iv. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (2 MCZ). Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the large body size (ca. 1.53 mm), the markedly cordiform pronotum, the very wide P 1 and P 2, and the aedeagus (Fig. 33). Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.53 / 0.69; head width 0.36; pronotum 0.38 / 0.52, PA 0.41, PB 0.38; elytra 0.90 / 0.69. Habitus as illustrated (Fig. 33). Pronotum markedly cordiform, width at midlength much wider than anterior and posterior margins. Dorsum dark brown to black, except labrum, clypeus, and maxillary palpi light brown to testaceous, tip of last palpomere not darker. Frons moderately finely moderately sparsely punctate, punctures ca. 1 xef. Pronotum coarsely densely punctate, especially anterior and posterior to moderately convex disc, interstices in densely punctate areas narrow walls; interstices on disc ca. 1 xpd, shining; punctures laterally much smaller and sparser. Punctures of clypeus very fine, moderately dense on disc, very dense laterally. Labrum apicomedian excision deep and wide, free margins weakly upturned, angulate laterally and medially. Pronotum anterior margin weakly emarginate over middle 1 / 2; antero- and posterolateral pronotal foveae deep, shallowly confluent; posterosubmedial foveae deep, area between antero- and posterolateral foveae distinctly convex. Elytra with posterior declivity rather abrupt, summit at or very near midlength; lateral explanate margins wide; on basal 1 / 3 punctures 1 xpd or slightly larger and deeper than largest pronotal punctures, punctures becoming gradually slightly smaller laterally and toward posterior. Intervals not raised, width on disc ca. 1 xpd, much wider laterally and posteriorly, interstices between punctures of a row ca. 1 – 6 xpd, each puncture with very short and very fine seta. Apices in dorsal aspect conjointly rather sharply rounded, in posterior aspect margins forming shallow angle with one another. Venter: Mentum finely sparsely punctulate, shining. Postmentum densely micropunctulate, dull. Genae very slightly raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.1 / 0.2 / 1.5. P 1 and P 2 very wide. P 2 l / w ca. 1 / 1, sides parallel, apex blunt. Plaques very small, very short, widely separated carinate lines, located at sides of deep median depression. AIS very wide, weakly concave, width at straight posterior margin ca. 1.2 x P 2. Tibiae slender, straight. Protibia very slightly widened and bearing short spine at ca. distal 2 / 3. Mesotibia slightly widened at ca. distal 2 / 3. Abdominal apex symmetrical, with rather wide and deep apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7850C5B847C1FADD263B.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90A7850C5B847C1FADD263B.taxon	etymology	Etymology. Named in reference to the known distribution, and to the markedly cordiform pronotum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	description	Figs. 5, 34 (habitus), 34 (aedeagus), 40 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. W. Prov., 7 km. E. Bamenda, stream, 30. i. 1982, leg. P. D. Perkins ” (MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the comparatively large body size (ca. 1.65 mm), the finely sparsely punctulate frons and pronotum, punctures very consistent in size throughout, interstices shining, the anterolateral foveae moderately deep, posterolateral and posterosubmedian foveae very shallow or absent, the very narrow plaques, with margins very ill-defined, and the aedeagus (Fig. 34).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.65 / 0.69; head width 0.38; pronotum 0.38 / 0.53, PA 0.42, PB 0.48; elytra 0.98 / 0.69. Habitus as illustrated (Fig. 34). Dorsum brown to dark brown, head, pronotal fascia and elytra dark brown, pronotum rather widely bordered anteriorly and posteriorly in light brown, maxillary palpi testaceous, tip of last palpomere not darker. Frons and pronotum finely sparsely punctulate, punctures of pronotum slightly larger than those of frons, very consistent in size throughout, interstices shining, ca. 1 – 3 xpd. Clypeus medially very finely sparsely punctulate, shining; laterally densely micropunctulate, dull. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae moderately deep, posterolateral and posterosubmedian foveae very shallow or absent. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins wide; on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals shining, not raised, width ca. 2 – 3 xpd, as are interstices between punctures of a row. Apices in dorsal aspect rather sharply conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely very densely micropunctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.3 / 1.3 / 1.3. P 1 laminate; median carina sinuate in profile. P 2 moderately wide, l / w ca. 2 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques very narrow, margins very ill-defined, slightly arcuate, slightly converging toward one another anteriorly, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1 x P 2. All tibiae slender. Protibia and mesotibia very weakly arcuate. Metatibia straight. Abdominal apex symmetrical, with deep, narrow apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 40).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9097851C5B841A5FF0425D7.taxon	etymology	Etymology. Named in reference to the known distribution, and to the two finger-like processes of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	description	Figs. 5, 35 (habitus), 35 (aedeagus), 40, 42 (maps)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: N. Prov., 35 km N. Ngaoundere, stream, 1. v. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (2 MCZ); N. W. Prov., Bamenda, stream nr. Skyline Hotel, 1. ii. 1982, leg. P. D. Perkins (4 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the narrow P 2 (l / w ca. 4 / 1), the very small, short and narrow plaques, the deep anterolateral pronotal foveae, and the aedeagus (Fig. 35). Similar in habitus to H. camerosetosa, but differing therefrom in ventral and aedeagal characters.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.25 / 0.56; head width 0.34; pronotum 0.32 / 0.43, PA 0.37, PB 0.38; elytra 0.76 / 0.56. Habitus as illustrated (Fig. 35). Dorsum brown to dark brown, frons and pronotal disc often darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum moderately finely and moderately sparsely punctulate, interstices shining; punctures of frons disc and pronotal disc ca. 1 xef, interstices ca. 1 – 2 xpd; clypeus dull, punctures very fine and dense. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral pronotal foveae deep, posterolateral and posterosubmedial pronotal foveae moderately deep Elytra with posterior declivity very gradual, summit of at or very near midlength; lateral explanate margins moderately wide; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 1 – 2 xpd or slightly greater, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins not forming angle with one another. Venter: Mentum very sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, moderately shining. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.5 / 1 / 1.5. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 4 / 1, sides parallel, blunt apex raised slightly above mesoventral intercoxal process. Plaques very small, short, narrow, not raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.5 x P 2. All tibiae slender, straight. Abdominal apex symmetrical, with apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	distribution	Distribution. Currently known only from the type locality and a site at Bamenda (Figs. 40, 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087851C5B84309FA652033.taxon	etymology	Etymology. Named in reference to the known distribution, and to the finger-like main-piece of the aedeagus.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	description	Figs. 5, 36 (habitus), 36 (aedeagus), 42 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., 15 km. S. Mbalmayo, Nyong River, ex. leaves at margin, 22. v. 1982, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (2 MCZ); Akonolinga, moist secondary forest and plantation, at light, 7. i. 1978, leg. Gardensforhall & Samuelson (1 LUM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the small size (ca. 1.05 mm, smallest species in Cameroon), the very narrow, very short, carinate or subcarinate, and widely separated plaques (P 2 / w / l / s ca. 1 / 0.2 / 2 / 2), and the male genitalia (Fig. 36).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.05 / 0.45; head width 0.27; pronotum 0.27 / 0.37, PA 0.31, PB 0.33; elytra 0.77 / 0.45. Habitus as illustrated (Fig. 36). Dorsum light brown to brown, head, pronotal macula and elytra dark brown, pronotum rather widely margined in light brown to testaceous, palpi testaceous, tip of last palpomere not darker. Dorsum of head finely moderately sparsely punctulate, pronotum moderately finely, moderately densely punctate, punctures ca. 1 xpd of largest punctures of frons, interstices shining, ca. 1 – 3 xpd. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral foveae moderately deep, posterolateral shallow or absent, posterosubmedian foveae shallow, medially confluent forming U-shaped impression. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins narrow; on basal 1 / 3 punctures slightly larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect separately rounded, in posterior aspect margins forming weak angle with one another. Venter: Mentum moderately sparsely very finely punctulate, shining; postmentum very finely densely micropunctulate, dull. Genae raised, shining, without posterior ridge. Ratios of P 2 width and plaque shape (P 2 / w / l / s) ca. 1 / 0.2 / 2 / 2. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 2 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques very narrow, slightly arcuate, slightly converging toward one another anteriorly, raised, located at sides of deep median depression. AIS width at straight posterior margin ca. 1.5 x P 2. Protibia slender, very weakly arcuate. Meso- metatibiae slender, straight. Abdominal apex symmetrical, with very small apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 42).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B9087856C5B847ADFACD2763.taxon	etymology	Etymology. Named in reference to the known distribution, and to the very long aedeagal flagellum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	description	Figs. 5, 37 (habitus), 37 (aedeagus), 41 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	materials_examined	Type Material. Holotype (male): “ Cameroon: C. S. Prov., Yaounde: Bastos, puddle, 12. xii. 1981, leg. P. D. Perkins ” (MCZ). Paratypes: Same data as holotype (10 MCZ).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the very sparcely and very finely punctulate head and pronotum, interstices strongly shining, the anterolateral pronotal foveae moderately deep, posterolateral and posterosubmedial foveae absent, the absence of metaventral plaques, and the aedeagus (Fig. 37).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.33 / 0.59; head width 0.34; pronotum 0.35 / 0.47, PA 0.38, PB 0.43; elytra 0.80 / 0.59. Habitus as illustrated (Fig. 37). Dorsum brown to light brown, frons and diffusely margined pronotal macula slightly darker, palpi testaceous, tip of last palpomere not darker. Dorsum of head and pronotum sparcely finely punctulate, pronotum more finely sparsely punctulate on macula than on surrounding areas, interstices shining; punctures of pronotal disc ca. 1 xef, interstices ca. 3 – 5 xpd or slightly larger; punctures of frons disc slightly larger and more closely spaced than those of pronotal disc; punctures of clypeus very fine, nearly obsolete. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral pronotal foveae moderately deep, posterolateral and posterosubmedial foveae absent. Elytra with summit of posterior declivity at or very near midlength; lateral explanate margins narrow; punctures fine, on basal 1 / 3 punctures ca. 1 xpd of largest pronotal punctures, punctures becoming gradually smaller toward posterior, each puncture with very short and very fine seta. Intervals not raised, width ca. 2 – 4 xpd, as are interstices between punctures of a row. Apices in dorsal aspect separately rounded, in posterior aspect margins forming moderately strong angle with one another. Venter: Mentum and postmentum sparsely finely punctulate, shining. Genae raised, shining, without posterior ridge. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides parallel, apex blunt, apex raised slightly above mesoventral intercoxal process. Plaques absent, median depression deep. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender. Pro- and mesotibiae very slightly arcuate, metatibia straight. Abdominal apex symmetrical, with shallow apicomedian notch.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 41).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7856C5B8409DFB1823E3.taxon	etymology	Etymology. Named in reference to the known distribution, and to the highly reflective dorsum.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	description	Figs. 5, 38 (habitus), 38 (aedeagus), 43 (map)	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	materials_examined	Type Material. Holotype (male): Cameroon: Northwest Province. “ BRITISH CAMEROONS / Matute, / Tiko Plantation / 5. v. 1949, B. Malkin ” (UKNHM). Paratypes: Same data as holotype (10 UKNHM).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	diagnosis	Differential Diagnosis. Differentiated from other members of the genus in Cameroon by the combination of the densely punctate dorsum, the absence of metaventral plaques, and the aedeagus (Fig. 38). H. camerosetosa differs from H. cameropetila, another species that lacks metaventral plaques, by a larger body size (ca. 1.33 vs. 1.20 mm), a markedly different aedeagus, and a wider mesoventral intercoxal process (P 2), which is twice as wide as the P 2 of H. cameropetila. Although H. cameropetila is smaller than H. camerosetosa in body length, the width of the mesocoxae are the same in the two species, making the ratio of P 2 width / mesocoxa width approximately 0.12 for H. cameropetila and 0.40 H. camerosetosa.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	description	Description. Size: holotype (length / width, mm): body (length to elytral apices) 1.33 / 0.55; head width 0.34; pronotum 0.34 / 0.46, PA 0.39, PB 0.42; elytra 0.78 / 0.55. Habitus as illustrated (Fig. 38). Dorsum testaceous to black, head and pronotal macula dark brown to black, pronotum rather widely margined in light brown to testaceous, elytra brown, palpi testaceous, tip of last palpomere not darker. Dorsum of head finely sparsely punctulate, pronotum moderately coarsely, densely punctate, punctures much larger than those of frons, interstices shining, ca. 1 xpd or less. Labrum apicomedially excised, free margins weakly upturned. Pronotum with anterior margin weakly emarginate over middle 1 / 2; anterolateral, posterolateral, and posterosubmedial foveae very shallow. Elytra with summit of posterior declivity slightly beyond midlength; lateral explanate margins narrow; on basal 1 / 3 punctures larger than largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, width ca. 1 xpd or less, as are interstices between punctures of a row. Apices in dorsal aspect separately rounded, in posterior aspect margins forming distinct angle with one another. Venter: Mentum finely punctulate, shining. Postmentum densely micropunctulate, dull. Genae raised, dull, without posterior ridge. Metaventral plaques absent. P 1 laminate; median carina sinuate in profile. P 2 l / w ca. 3 / 1, sides slightly converging toward blunt apex, apex raised slightly above mesoventral intercoxal process. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at straight posterior margin ca. 2 x P 2. All tibiae slender, protibia very slightly arcuate, meso- and metatibiae straight. Abdominal apex with apicomedian indentation.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	distribution	Distribution. Currently known only from the type locality (Fig. 43).	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
0C081779B90F7857C5B84555FB43217E.taxon	etymology	Etymology. Named in reference to the entirely setose metaventrite, which lacks plaques.	en	Perkins, Philip D. (2022): Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae). Zootaxa 5203 (1): 1-66, DOI: 10.11646/zootaxa.5203.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5203.1.1
