Buea

Mvogo Ndongo, Pierre A, von Rintelen, Thomas, Tomedi-Tabi Eyango, Minette & Cumberlidge, Neil, 2020, Morphological and molecular analyses reveal three new endemic species of the freshwater crab genus Buea Cumberlidge, Mvogo Ndongo, Clark & amp; Daniels, 2019 (Crustacea: Brachyura: Potamonautidae) from a rainforest biodiversity hotspot in Cameroon, Central Africa, Journal of Crustacean Biology 40 (3), pp. 288-300 : 299

KEY TO THE SPECIES OF BUEA

1. Carapace highly arched (CH/FW 1.4–1.5), anterior carapace surface with fields of granules and carinae; distinct vertical (pleural) groove on carapace branchiostegite wall; thoracic sternal sulcus S2/S3 slightly arched; G1 TA extremely long, equal to SS length (TA/SS 1.0) ……………...…………………………..…………………… 2

– Carapace not highly arched (CH/FW 1.1–1.3), anterior carapace surface completely smooth; vertical (pleural) groove on carapace branchiostegite wall either faint or absent; thoracic sternal sulcus S2/S3 straight, horizontal; G1 TA long, but not equal to SS length (TA/SS 07–0.9) .........……………............. 3

2. Major cheliped propodus inferior margin distinctly concave; pollex with three evenly-spaced large teeth ( Fig. 3C ) ………… …………..……..………................................. B. bangem n. sp.

– Major cheliped propodus inferior margin straight or only slightly indented; pollex with large molar proximally, followed by 4 distinct teeth interspersed by smaller teeth ( Fig. 3E ) …………..................................................... B. mundemba n. sp.

3. Cervical, urogastric, cardiac, branchial carapace grooves either faint or absent (fig. 3A); postfrontal crest incomplete, not meeting anterolateral margins ( Figs. 3A , 5D, H ); major cheliped dactylus with 3 large teeth proximally, one tooth medially (3I); pollex of propodus with molar consisting of 3

– fused teeth proximally, followed by smaller teeth, with larger tooth in middle ( Fig. 3I )….......… B. asylos ( Cumberlidge, 1993) Cervical , urogastric, cardiac, branchial carapace grooves distinct, deep ( Figs. 2E , 5G ); postfrontal crest complete, meeting anterolateral margins ( Fig. 5C ); major cheliped dactylus cutting edge lined by small teeth, medium size tooth in middle; pollex of propodus with 3 large teeth proximally, followed by smaller teeth interspersed by 2 distinct teeth ( Fig. 3G ) ……….. ..............................................…..…………….. B. nlonako n. sp.

Figures

Figure 2. Buea bangem n. sp.: dorsal (A), ventral (B) views of adult male (CW 26.54 mm; ZMB Crust. 30325), Bakossi National Park, Southwest Region, Cameroon. Buea mundemba n. sp.: dorsal (C), ventral (D) views of adult male (CW 26.15 mm; ZMB Crust. 30321), Korup National Park, Southwest Region, Cameroon. Buea nlonak n. sp.: dorsal (E), ventral (F) views of adult male (CW 25.80 mm; ZMB Crust. 31786), Mt. Nlonako Ecological Reserve, Littoral region, Cameroon. This figure is available in color at Journal of Crustacean Biology online.

Figure 3. Buea asylos (Cumberlidge, 1993), holotype: dorsal (A) ventral (B) views of adult male (CW 27.6 mm; NHM 1994.587), between Buea and Kumba, Cameroon (photographs by Phillip Crabb, NHM, London (Cumberlidge et al., 2019: fig. 1a, b). Buea bangem n. sp.: frontal view of the major (C) and minor (D) chelipeds of adult male (CW 26.54 mm; ZMB Crust. 30325), Bakossi National Park, Southwest Cameroon. Buea mundemba n. sp.: frontal view of the major (E) and minor (F) chelipeds of adult male of (CW 26.15 mm; ZMB Crust. 30321), Korup National Park, Southwest Cameroon. Buea nlonako n. sp.: frontal view of the major (G) and minor (H) chelipeds of adult male of (CW 25.80 mm; ZMB Crust. 31786), Mt. Nlonako Ecological Reserve, Littoral Region, Cameroon. Buea asylos: frontal view of the major (I) and minor (J) chelipeds of adult male (CW 27.6 mm; NHM 1994.587) between Buea and Kumba, Southwest Cameroon region (Cumberlidge et al., 2019: figs. 1a, b, 5 a, b). This figure is available in color at Journal of Crustacean Biology online.

Figure 5. Frontal view showing details of the carapace of adult males of species of Buea: B. bangem n. sp. (CW 26.54 mm; ZMB Crust. 30325) (A); B. mundemba n. sp. (CW 26.15 mm; ZMB Crust. 30321) (B); B. nlonako n. sp (CW 25.80 mm; ZMB Crust. 31786) (C); B. asylos (CW 27.6 mm; NHM 1994.587) (Cumberlidge et al., 2019: fig. 4a) (D). Dorsal view showing details of the carapace of adult males of species of Buea: B. bangem n. sp. (CW 26.54 mm; ZMB Crust. 30325) (E); B. mundemba n. sp. (CW 26.15 mm; ZMB Crust. 30321) (F); B. nlonako n. sp. (CW 25.80 mm; ZMB Crust. 31786) (G); B. asylos (CW 27.6 mm; NHM 1994.587) (Cumberlidge et al., 2019: fig. 1a) (H). Ventral view showing details of the anterior thoracic sternum and distal part of the pleon of adult males of species of Buea: B. bangem n. sp. (CW 26.54 mm; ZMB Crust. 30325) (I); B. mundemba n. sp. (CW 26.15 mm; ZMB Crust. 30321) (J); B. nlonako n. sp. (CW 25.80 mm; ZMB Crust. 31786) (K); B. asylos (CW 27.6 mm; NHM 1994.587) (Cumberlidge et al., 2019: fig. 1b) (L). This figure is available in color at Journal of Crustacean Biology online.