taxonID	type	description	language	source
03F587F0FF93FFFDFE228398FE6F402F.taxon	description	(Figures 1 – 13) Species examined Hydrocassis jengi Satô, 1998 (L 2), Hydrocassis lacustris (Sharp, 1884) (L 1 – 3), Hydrocassis uncinata Ji and Schödl, 1998 (L 2 – 3). Diagnosis Larvae of Hydrocassis can be distinguished from those of other known genera of the tribe Sperchopsini by the following combination of character states: (1) frontal lines fused at base (Figures 2 A, 6 B); (2) nasale with four to five teeth (Figures 2 C, 4 C, 6 C, 10 C); (3) clypeolabrum almost symmetrical (Figures 2 C, 6 C); (4) epistomal lobes with rather slender setae (Figure 4 C); (5) mandibles with three inner teeth (Figure 5 B, C); (6) inner surface of stipes with five setae in all instars (Figures 3 C, 5 D, 7 D); (7) dorsal sclerite of abdominal segment 8 not subdivided medially (Figure 4 D). Description of general morphology Body rather slender, widest between abdominal segments 3 and 4 (Figure 1). Lateral sides of meso- and metathorax and abdominal segments 1 to 8 with lateral projections on each segment (Figures 4 A, 6 A, 10 A). Nine pairs of spiracles, one on anterolateral portion of mesothorax and eight on abdomen; mesothoracic and first seven abdominal spiracles non-functional, biforous; last pair annular, large and functional, enclosed within spiracular atrium. Head. Head capsule subquadrate (Figures 4 B, 6 B, 10 B). Frontal lines almost V-shaped, fused at base of head capsule; coronal line short. Dorsal and lateral surfaces of head capsule bearing dense, small, strong to rather strong, tooth-like cuticular projections (e. g. Figures 8 C, 9 B). Six stemmata on each anterolateral corner of head capsule. Clypeolabrum slightly asymmetrical. Nasale with four to five teeth, median tooth small or absent (Figures 6 C, 10 C). Epistomal lobes rounded, almost symmetrical, projecting about as far as nasale or slightly lower than nasale; inner part of each lobe with spine-like cuticular projections. Antenna. Three-segmented, rather short and stout (first instar, Figure 3 A) to moderately long and slender (third instar, e. g. Figure 7 A). Antennomere 1 the longest, longer than antennomeres 2 and 3 combined (third instar) to almost about as long as antennomere 2 (first instar). Antennomere 3 the shortest, small. Surface of antenna with small, spin-like cuticular projections (e. g. Figure 9 C). Mandibles. Symmetrical, with three inner teeth, two distal ones large, basal one small (e. g. Figure 5 B – C). Maxilla. Counting cardo, six-segmented, distinctly longer than antenna (e. g. Figures 3 C, D, 5 D, E). Cardo large, irregularly shaped, subtriangular to subquadrate. Stipes the longest, longer than palpomeres 1 – 4 combined, with one spine-like cuticular projection on apex of inner surface, and narrow and dense cuticular projections in basal part of inner surface, between sensilla MN 7 and MN 8. Maxillary palpus four-segmented; palpomere 3 the longest, palpomere 2 the shortest; palpomere 1 the widest, palpomere 4 the narrowest; palpomere 1 incompletely sclerotized on dorsal surface, bearing small hair-like cuticular projections on anterior part of dorsal surface of intersegmental membrane between palpomeres 1 and 2 (e. g. Figure 7 D); inner process sclerotized; dorsolateral surface of intersegmental membrane of palpomeres 2 and 3 bearing fine hair-like cuticular projections; palpomere 3 slightly longer than palpomeres 1 and 2 combined, narrower than palpomere 2. Labium. Well developed (Figures 2 B, 3 E – F, 7 F – G). Submentum fused to head capsule, large, subpentagonal, wider than mentum (Figure 2 B). Mentum trapezoidal in dorsal view, with short, stout tooth-like cuticular projections on dorsal surface except on median part. Prementum subquadrate, bearing fine hair-like cuticular projections on dorsolateral part of intersegmental membrane between prementum and labial palpi. Ligula shorter than palpi, mostly sclerotized. Labial palpi moderately short, slender; palpomere 1 small; palpomeres and intersegmental membrane between palpomere 1 and 2 densely covered with fine hair-like cuticular projections (Figure 5 F). Thorax. Prothorax trapezoidal, wider than head capsule. Proscutum formed by one large plate divided by fine sagittal line, covered with short setae (Figure, 9 D). Presternum subpentagonal (Figure 12 A), with long, almost complete sagittal line on sclerite. Mesothorax with three dorsal sclerites on each side; medioanterior sclerite small, narrow; anterolateral sclerite small; posterior sclerite large, subdivided by fine sagittal line, and with transverse ridge on anterior part; one small tubercle outside dorsal sclerite; four strong lateral projections on each side visible from dorsal view. Metathorax with two dorsal sclerites on each side; anterior sclerite large, subdivided by sagittal line; posterior sclerite narrow, smaller than anterior one, behind tubercle; lateral sides of posterior sclerites with two large projections; four strong to rather weak lateral projections on each side visible from dorsal view. Legs (Figure 12 B – D): rather short, barely visible in dorsal view, five-segmented, bearing numerous stout setae. Abdomen. Ten-segmented, tapering towards posteriad, segments 8 to 10 forming spiracular atrium. Segments 1 to 7 similar in size and shape, each subdivided by transverse folds and bearing several tubercles (Figure 4 E). Segment 1 with three lateral projections on each side dorsally, and with one pair of small dorsal sclerites medioanteriorly, the sclerites larger than those on segments 2 to 7, and three transverse rows of tubercles behind the sclerites; sclerites larger than those on segments 2 to 7. Segments 2 to 6 almost similar to segment 1. Segment 7 with one pair of small dorsal sclerites medioanteriorly, with three transverse rows of tubercles, third row of the tubercles with two tubercles on each side, outer one projected laterad. Spiracular atrium (Figure 4 D). Segment 8 with a large, oval dorsal plate, rather densely covered with short setae, posterior edge of the plate weakly rounded. Segment 9 trilobed, largely sclerotized on dorsum, partially covered by segment 8, with a pair of short, one-segmented urogomphi; urogomphi with three very long setae; procercus incompletely sclerotized, with two setae. Segment 10 reduced. Description of primary chaetotaxy of head (Based on first instar larvae of H. lacustris; slide preparations of eight specimens were examined.) Frontale with 52 – 54 sensilla (Figure 2 A, C). Central part with three pairs of sensilla (FR 1 – 3) divergent posteriad; FR 1 trichoid, short seta, situated close to frontal line; FR 2 pore-like, situated mesally of line connecting FR 1 and FR 3; FR 3 trichoid, moderately stout seta, situated more anteriorly and slightly more mesally than FR 2. FR 4 – 6 situated posteromesally to antennal socket, forming a triangular group; FR 4 pore-like; FR 5 rather short seta; FR 6 rather long seta. FR 7 rather short seta situated on inner margin of antennal socket. FR 8 long seta situated posteriorly to two median teeth of nasale. Nasale with a group of eight setae (gFR 1) (Figure 2 C); six setae rather short, stout, intercalated between teeth; one short seta situated ventrally on inner margin of each large median tooth. Each epistomal lobe with a group of seven to eight moderately long, stout setae (gFR 2), inner three slightly shorter than outer ones. FR 15 pore-like, placed posteriorly to median setae of gFR 1. FR 9 – 10 and FR 14 situated mesally to antennal socket; FR 9 pore-like, located between FR 10 and FR 12; FR 10 rather long, trichoid seta, situated posteriorly to FR 9; FR 14 porelike, located laterally of FR 9 – 10 and FR 12, close to FR 7. FR 11 placed in inner part of epistomal lobe, anteriorly to FR 9 – 10; FR 11 pore-like, situated posterolaterally to outer seta of gFR 1; FR 13 pore-like, placed between FR 11 and FR 9; FR 12 short seta, located laterally of line connecting FR 11 and FR 13. Parietale. With 30 sensilla each (Figure 2 A, B). Dorsal surface with a group of sensilla (PA 1 – 5) located posteriorly at mid-width, forming a slightly irregular longitudinal row; PA 3 pore-like, situated slightly anteriorly to PA 2; PA 1 – 2 and PA 4 – 5 short setae. PA 6 pore-like, situated posteromesally, close to joint of frontal and coronal lines. PA 7 moderately long seta close to frontal line, situated laterally of line connecting PA 6 and PA 8. PA 8 moderately long seta situated between frontal line and inner stemma of anterior row. PA 9 long seta, situated on outer edge of antennal socket. PA 10 pore-like, located between two innermost stemmata. PA 11 rather long seta, situated anteromesally to outer stemma of posterior row. PA 12 and PA 13 rather long, trichoid setae situated approximately at mid-length of parietale, behind PA 10 – 11 and stemmata. Anterolateral corner of epicranium with three sensilla (PA 19 – 21); PA 19 pore-like, situated more dorsally than others; PA 20 rather short, trichoid seta, situated between PA 19 and PA 21; PA 21 long, trichoid seta. Anterior one-third of lateroventral surface of parietale with four sensilla (PA 14 – 17); the sensilla forming a slightly irregular transverse row; PA 14 long seta; PA 15 pore-like, situated close to PA 14; PA 16 long seta, situated between PA 15 and PA 17; PA 17 pore-like; PA 15 – 17 situated more ventrally than PA 14. PA 18 long seta, situated at mid-length of lateral surface of parietale, posteriorly to PA 15 – 16, more ventrally than PA 14. PA 22 – 25 located ventrally along anterolateral portion of parietale; long seta PA 22 and pore-like sensillum PA 23 situated close to anterolateral corner; PA 24 – 25 pore-like, close to inner margin of mandibular acetabulum; PA 24 pore-like, located between PA 23 and PA 25, close to PA 25. Median part of parietale with three sensilla (PA 26 – 28), PA 26 long seta, situated more anteriorly than remaining sensilla, PA 27 pore-like, situated medially of line connecting PA 26 and PA 28; PA 28 rather long seta, located more posteriorly than remaining sensilla. One pore-like sensillum (PA 29) situated in basal one-third of parietale on ventral side behind PA 28. PA 30 pore-like, situated ventrally in about basal one-quarter of parietale. Antenna (Figure 3 A). Antennomere 1 with five pore-like sensilla (AN 1 – 5); AN 1 situated in basal one-third; AN 2 situated in distal one-third; AN 3 located apically on inner face, indistinct; AN 4 located subapically on outer face; AN 5 located subapically on ventral surface. Antennomere 2 with one pore-like sensillum (AN 6) situated dorsally in distal two-fifths. Five setae (AN 7 – 11) situated on intersegmental membrane between antennomeres 2 and 3; AN 7 – 8 small, stout, situated on outer face of antenna next to sensorium (SE 1); AN 9 small, situated mesally of AN 7 – 8. AN 10 – 11 on inner face of antenna; AN 10 long and trichoid, AN 11 short, both setae close to each other. SE 1 small, much shorter than antennomere 3, about as long as AN 7 and AN 8. Antennomere 3 with one pore-like additional sensillum placed dorsally close to distal margin of sclerite, and six sensilla on apical membranous area (gAN): two long setae, two minute conical setae, and two minute setae. Mandible (Figure 3 B). Bearing two setae (MN 1 and MN 5) and four pore-like sensilla (MN 2 – 4 and MN 6) situated on dorsal to lateral surface. MN 1 rather long on outer face. MN 2 – 4 forming a triangular group at mid-length on dorsal surface; MN 2 more closely attached to MN 1 than to remaining sensilla; MN 3 situated mesally of line connecting MN 2 and MN 4, MN 4 on outer face. MN 5 short seta, placed on outer margin in distal one-quarter of mandible. MN 6 pore-like, very small, situated subapically on inner face. Maxilla (Figure 3 C, D). Cardo with one moderately long, trichoid seta ventrally (MX 1). Stipes with a row of five setae (MX 7 – 11) situated dorsally along inner surface; MX 7 moderately short, shorter than MX 8 – 11, situated basally; MX 8 – 11 rather stout, spiniform, with subapical tooth, equidistant from each other. Ventral surface of stipes with two pore-like sensilla (MX 2 and MX 3) situated in basal 0.3 and distal 0.4, respectively; one pore-like sensilla (MX 4) and two long trichoid setae (MX 5 and MX 6) situated subapically on outer surface of sclerite; MX 4 situated posteriorly to MX 5 and MX 6, MX 5 between MX 4 and MX 6. Palpomere 1 with one rather stout, spiniform seta (MX 16) situated basally on inner face, and with one pore-like sensillum (MX 12) and two setae (MX 13 – 14) situated lateroventrally along distal margin of sclerite; MX 12 situated more dorsally than MX 13 and MX 14; MX 13 long seta, between MX 12 and MX 14; MX 14 moderately long seta. Two pore-like sensilla (MX 15 and MX 17) on membrane below inner appendage, MX 17 dorsal, MX 15 ventral. Appendage with one long and four minute setae apically (gAPP). Palpomere 2 with two pore-like sensilla (MX 18 and MX 19) and one minute seta (MX 27); MX 18 situated lateroventrally on anterior margin of sclerite; MX 19 situated apically on inner face of intersegmental membrane between palpomeres 2 and 3; MX 27 situated basally on outer face of sclerite. Palpomere 3 with four sensilla (MX 20 – 23); MX 21 – 22 rather short seta and pore-like sensillum respectively, both situated subapically at mid-width of ventral surface of sclerite; MX 22 located posteriorly to MX 21; pore-like sensillum (MX 20) and moderately long seta (MX 23) situated apically on outer face of sclerite; MX 23 dorsal, MX 20 ventral. Palpomere 4 with proximal rather long seta (MX 24) on inner face of sclerite, and with digitiform sensillum (MX 25) and pore-like sensillum (MX 26) situated subapically on outer face, MX 25 dorsal, MX 26 ventral. Apical membranous area of palpomere 4 with six minute setae (gMX). Labium (Figures 2 B, 3 E, F). Submentum with two pairs of setae (LA 1 – 2); LA 1 long, on lateral corners; LA 2 moderately short, on anterior corners (Figure 2 B). Mentum with two pairs of sensilla (LA 3 – 4) situated ventrally in distal one-fifth of sclerite; LA 3 rather long seta, located more mesally than pore-like sensillum LA 4. Dorsal surface of prementum with one pair of pore-like sensillum (LA 8) and small seta (LA 9); LA 8 situated subbasally at midwidth of sclerite; LA 9 on lateral part of membrane between prementum and palpi. Ventral surface of prementum with three pairs of sensilla (LA 5 – 7); LA 5 rather short seta, situated proximo-laterally; long seta LA 6 and porelike sensillum LA 7 situated laterally on distal margin of sclerite; LA 6 situated more mesally than LA 7. Long seta (LA 10) situated dorsally at base of ligula. Ligula with two pairs of pore-like sensilla (LA 11 – 12); LA 11 situated ventrally close to mid-length of ligula; LA 12 situated dorsally in apical membranous area. Labial palpomere 1 with a minute seta (LA 13) on base of ventral surface of palpomere. Pore-like sensillum LA 14 situated dorsally on intersegmental membrane between palpomeres 1 and 2. Palpomere 2 with one pore-like sensillum (LA 15), situated subapically on outer face; apical membranous area with several small setae (gLA). Variation Hydrocassis shows a weak intra-specific variation (e. g. Figures 6 C, 10 C) in the following characters: (1) Number of teeth of nasale: in some specimens the small median tooth is reduced, therefore in this case, the number of teeth on nasale is four; (2) number of setae of epistomal lobe (gFR 2): it ranges from six to nine based on the specimens examined in this study.	en	Minoshima, Yûsuke, Hayashi, Masakazu (2011): Larval morphology of the genus Hydrocassis Fairmaire (Coleoptera: Hydrophilidae). Journal of Natural History 45 (45 - 46): 2757-2784, DOI: 10.1080/00222933.2011.602805, URL: http://dx.doi.org/10.1080/00222933.2011.602805
03F587F0FF85FFFBFE59851FFBC546C4.taxon	description	Figures 1 B, 4, 5, 12 A, B Material examined Japan: 1 L 2 (SEHU), Kinsakubaru, Amami-Ôshima I., Kagoshima pref., 30 April 1999, no collector data; 1 L 2 (EUMJ), Akatsuchi-yama, Uken-son, Amami-Ôshima I., Kagoshima pref., 2 May 1999, no collector data.; 1 L 2 (SEHU), upstream of Naon-kawa R., Yamato-son, Amami-Ôshima I., Kagoshima pref., 30 July 2008, J. Fujiwara leg. Description of general morphology of second instar Slide preparations of two specimens were examined. Colour (Figure 1 B). Dorsal surface of head light brown, lighter in median and anterior parts of frontale and around stemmata, with two pairs of dark brown spots medioposteriorly; light brown ventrally. Pronotum light yellowish brown, median portion darkened; meso- and metathoracic terga and abdominal segments light yellowish brown to dark brown, lighter medially and laterally, so looking as two dark longitudinal lines along the body; sclerotized parts darker than median part of abdomen; dorsal sclerite of abdominal segment 8 dark brown in medioposterior part. Ventral surface of thorax and abdomen greyish white to yellowish white, proscutum and legs darkened. Head. Posterior half to two-thirds of head capsule bearing dense, small but strong tooth-like cuticular projections on dorsal and lateral surfaces behind stemmata (Figure 4 B). Nasale with four teeth. Epistomal lobes not projecting further than nasale, each lobe with dense, rather short to short spine-like cuticular projections on inner margin (Figure 4 C). Antenna (Figure 5 A). Ventral and lateral surfaces of antennomeres 1 and 2 covered with fine hair-like cuticular projections, the projections on antennomere 2 denser than those on antennomere 1. Antennomere 1 the longest, longer than antennomeres 2 and 3 combined. Antennomere 2 about 0.6 times as long as antennomere 1. Abdomen. Segment 1 with three transverse rows of tubercles behind the sclerites (Figure 4 E); the first row with four rather large tubercles on each side, outer one larger than inner three; second row with four tubercles on each side, inner three more closely situated than outer one, the size of the tubercles from median to lateral one,: rather large (L), L, rather L, L; third row with three large tubercles on each side, outer one projecting laterally. Arrangement of tubercles on segments 2 to 5 similar to that on segment 1 but first row with five tubercles, tubercles somewhat larger than those on segment 1: L, rather L, L, L, L. Segment 6 similar to segments 2 to 5 but tubercles of first row smaller than those on segments 2 to 5; inner four rather large, outer one large; outer two closely located. Segment 7 with three transverse rows of tubercles, the first row with five tubercles on each side, outer two closely located: rather L, very small (S) (hardly recognizable, absent on left side in specimen examined this study), rather L, rather L, L; second row with four tubercles, inner three closely located: S, L, very S (hardly recognizable, absent on left side in specimen examined for this study), L; third row with two tubercles each side, outer one projecting laterally. Description of chaetotaxy of head of second instar Frontale. Lateral part bearing numerous rather short secondary setae behind sensilla FR 4 – 6 (e. g. Figure 9 B). Each epistomal lobe with group of six to seven moderately long setae (gFR 2), inner two slightly shorter than outer setae. Parietale. Bearing many secondary sensilla, on dorsal and lateral parts. Mandible (Figure 5 B, C). With several small secondary setae on lateral part; basal part of mandible with seven rather short secondary setae, three on dorsal, four on ventral face. Maxilla (Figure 5 D, E). Stipes with 10 – 11 long secondary setae on outer face; one of them very long, close to MX 5 – 6. Labium (Figure 5 F, G). Mentum with nine stout secondary setae in each anterolateral corner; a trichoid secondary seta situated ventrally, close to and outside LA 4. Habitat Running water. A larva was found in the root of a tree in the bank of a stream (Naonkawa River) (J. Fujiwara, personal communication). Identification Hydrocassis jengi is the only species of the genus distributed in the Amami Islands, southeastern Japan. We identified the larval instar by presence or absence of secondary sensilla and comparing the size of their head capsule with those of H. lacustris and H. uncinata, of which the larvae and adults of each species are almost the same size.	en	Minoshima, Yûsuke, Hayashi, Masakazu (2011): Larval morphology of the genus Hydrocassis Fairmaire (Coleoptera: Hydrophilidae). Journal of Natural History 45 (45 - 46): 2757-2784, DOI: 10.1080/00222933.2011.602805, URL: http://dx.doi.org/10.1080/00222933.2011.602805
03F587F0FF83FFF8FE24839CFD1347BA.taxon	description	Figures 1 A, 2, 3, 6 – 9, 12 C, D, 13 A, C Material examined Japan: 1 L? (SEHU), Yunosato, Shiriuchi-chô, Hokkaidô, 19 June 2008 H. Yoshitomi leg; 1 L 1, 2 L 3 (EUMJ, SEHU), Yazawa-sawa, Kuroiso, Tochigi pref., 25 July 1994, M. Satô leg.; 1 L 1 (EUMJ), Shiga-kôgen, Yamanouchi-machi, Nagano pref., 4 – 5 August 1978, no collector data; 12 L 1, 4 L 2 (reared from egg case) (SEHU), small stream near Abe-tôge, Umegashima, Aoi-ku, Shizuoka-shi, Shizuoka prefecture, altitude 1380 m, 35 ◦ 18.81 ′ N, 138 ◦ 20.96 ′ E, 22 June 2008 (egg case collected), Y. Minoshima leg.; 1 L 3 (EUMJ), Dando-uradani, 15 July 1998, no collector data; 1 L 3 (EUMJ), Serŷo-toge, Kyôto, 6 August 1980, no collector data; 1 L 1, 1 L 2, 3 L 3 (HGFC, SEHU), Shinji-gawa R., Matsue-shi, Shimane pref., 5 May 2007, M. Hayashi leg.; 1 L 3 (SEHU), Mount Ôyorogi-san, Kadosaka, Iinan-chô, Shimane pref., 31 July 2007, M. Hayashi leg. Description of general morphology – third instar Slide preparations of three specimens were examined. Colour (Figure 1 A). Dorsal surface of head light brown, lighter in median and anterior parts of frontale and around stemmata, with two pairs of dark brown spots on medioposterior portion; light brown on ventral surface. Pronotum light brown, median portion darkened, the size of dark portion variable, sometimes resembles H. jengi (Figure 1 B); mesothoracic and metathoracic terga and abdominal segments dark brown, darker than head, slightly lighter medially and laterally, looking like two dark longitudinal lines along the body; dorsal sclerite and tubercles of abdominal segments darker than those on other abdominal portions; dorsal sclerite of abdominal segment 8 dark brown in median portion. Ventral surface of thorax and abdomen light brown, proscutum and legs darkened. Head. Posterior 0.5 to 0.6 of head capsule bearing dense, small but strong tooth-like cuticular projections on dorsal and lateral surfaces behind stemmata (Figure 9 B). Nasale usually with five teeth, median tooth very small, sometimes absent, then nasale with four teeth. Epistomal lobes projecting about as far as nasale, right lobe with dense rather long spine-like cuticular projections on inner margin; left lobe with dense, short spine-like cuticular projections on inner margin. Antenna. Antennomeres 1 and 2 covered with fine hair-like cuticular projections (Figures 7 A, 9 C). Antennomere 1 the longest, longer than antennomeres 2 and 3 combined. Antennomere 2 about half as long as antennomere 1. Maxilla (Figure 7 D, E). Dorsal surface of maxillary palpomeres 1 – 3 bearing sparse to rather dense fine hair-like cuticular projections. Labium (Figure 7 F, G). Ligula slightly shorter than palpi. Abdomen. Segment 1 with three transverse rows of tubercles behind the sclerites (Figure 6 E); the first row with five tubercles on each side, size of the tubercles from median to lateral one: large (L), small (S), rather L, S, L; second row with four tubercles on each side, inner three more closely situated than outer one: rather L, L, rather L, L; third row with three large tubercles on each side, outer one projecting laterally. Arrangement of tubercles on segments 2 to 5 similar to that on segment 1 but the tubercles of first and second transverse rows somewhat larger than those on segment 1: rather L, rather S, rather L, rather L, L in first row; rather L, L, L, L in second row. Segment 6 similar to segments 1 to 5 but first row composed of four rather large tubercles. Segment 7 with three transverse rows of tubercles, first row with four tubercles on each side, outer two closely situated: rather L, rather L, rather L, L; second row with four tubercles, inner three closely located: S, L, S, L; third row with two tubercles on each side, outer one projecting laterally. Description of general morphology – second instar Slide preparations of two specimens were examined. Similar to third instar, more weakly sclerotized than in third instar. Head. Antenna moderately long, rather slender. Antennomere 2 about 0.5 to 0.6 times as long as antennomere 1. Maxilla. Dorsal surface of maxillary palpomeres 1 and 2 sparsely covered with fine hair-like cuticular projections. Abdomen. Abdominal transverse rows of tubercles smaller than in third instar. Description of general morphology – first instar Slide preparations of eight specimens were examined. Similar to third instar, more weakly sclerotized than in second instar. Head (Figure 2). Frontal lines almost reaching to antennal socket. Antenna (Figure 3 A). Rather short and stout, bearing fine hair-like cuticular projections on ventral surface of antennomere 2. Antennomere 1 wider than antennomere 2, as long as antennomere 2. Abdomen. Abdominal transverse rows of tubercles smaller than in second instar; inner two pairs of tubercles of the second row on segments 1 to 5 reduced, hardly recognizable. Description of chaetotaxy of head – second instar Frontale. Central part bearing numerous, rather short secondary setae (e. g. Figure 9 B). Each epistomal lobe with a group of seven to eight moderately long, stout setae (gFR 2), inner two slightly shorter than outer ones. Parietale. Bearing many secondary sensilla, on dorsal and lateral parts (e. g. Figure 9 A, B). Mandible. With several small secondary setae on lateral part; basal part of mandible with four to five short secondary setae (e. g. Figure 7 B, C). Maxilla. Stipes with 10 – 12 long secondary setae on outer face; one of them very long, close to MX 4 – 6 (e. g. Figure 7 D, E). Labium. Mentum with 9 – 12 stout secondary setae each anterolateral corner; a trichoid secondary seta on ventral close to and outside of LA 4 (e. g. Figure 7 F, G). Description of chaetotaxy of head – third instar Frontale. Central part bearing many, rather short and stout secondary setae (Figure 9 B). Each epistomal lobe with a group of seven to eight moderately long, stout setae (gFR 2), inner two slightly shorter than outer ones. Parietale. Bearing numerous, rather short and stout secondary sensilla each, on dorsal and lateral parts (Figure 9 A, B). Mandible (Figure 7 B, C). With rather sparse, small secondary setae on lateral part; basal part of mandible with five short secondary setae, three on dorsal and lateral, two on ventral. Maxilla (Figure 7 D, E). Stipes with 13 – 15 long secondary setae on outer margin. Labium (Figure 7 F, G). Mentum with 8 – 12 stout secondary setae on each anterolateral corner. Habitat Running water (Figure 13 A). Egg cases were found on the underside of rocks or leaves on the margins of a stream (Figure 13 C); larvae usually hide behind rocks or leaves. Identification Hydrocassis lacustris is the only species of the genus distributed from Hokkaidô to Kyûshû Islands. Therefore, we identified the larvae collected from Honshû as H. lacustris. Instars of the larvae collected in the field were identified by sorting the specimens according the size of their head capsule and by comparison with the larvae of the known instar reared from egg cases collected in the field. Remarks Morioka (1955) published a description of the larva of “ Hydrocyclus sp. ” based on the specimens collected in Shiga and Tochigi Prefectures, Honshû. This larva corresponds in all characters with our material of H. lacustris. Later, Yoshimura (1959) described the larva collected in Nara Prefecture, Honshû as “ Hydrocyclus sp. B ”. Based on his description, his material differs substantially from Hydrocassis and belongs most probably to the genus Sternolophus Solier, 1834.	en	Minoshima, Yûsuke, Hayashi, Masakazu (2011): Larval morphology of the genus Hydrocassis Fairmaire (Coleoptera: Hydrophilidae). Journal of Natural History 45 (45 - 46): 2757-2784, DOI: 10.1080/00222933.2011.602805, URL: http://dx.doi.org/10.1080/00222933.2011.602805
03F587F0FF80FFF4FE518296FE9246ED.taxon	description	Figures 1 C, 10, 11, 13 B Material examined Laos: 1 L 2, 2 L 3 (SEHU), upstream of Nam Xan R., northwest Mount Phou Samsoun, Xieng Khouang province, altitude 2050 m, 19 ◦ 08.42 ′ N, 103 ◦ 47.13 ′ E, 13 May 2008, Y. Minoshima leg. (MiYu-L- 08 - 010); 2 L 3 (SEHU), upstream of Nam Mo R., northeast Mount Phou Samsoun, Xieng Khouang province, altitude 2200 m, 19 ◦ 08.47 ′ N, 103 ◦ 48.46 ′ E, 15 May 2008, Y. Minoshima leg. (MiYu-L- 08 - 015); 1 L 2 (SEHU), north Mount Phou Samsoun (small stream), Xieng Khouang province, altitude 2210 m, 19 ◦ 08.73 ′ N, 103 ◦ 48.24 ′ E, 15 May 2008, Y. Minoshima leg. (MiYu- L- 08 - 016). Description of general morphology – third instar Slide preparations of three specimens were examined. Colour (Figure 1 C). Dorsal surface of head light brown, darker in median part, with two pairs of dark brown spots on medioposterior portion; ventral surface slightly lighter than dorsal surface. Pronotum light brown, medioanterior portion darkened, dark portion spotted, rather variable in their positions; mesothoracic and metathoracic terga and abdominal segments light yellowish brown, lighter than head, slightly lighter medially and laterally; mesotergum with two dark areas on median part; dorsal sclerites and tubercles of abdominal segments somewhat darker than other abdominal portions; dorsal sclerite on abdominal segment 8 dark brown in median portion. Ventral surface of thorax and abdomen light yellowish brown, proscutum and legs darkened. Head. Posterior 0.5 to 0.6 of head capsule bearing dense, small tooth-like cuticular projections on dorsal and lateral surfaces behind stemmata (Figure 10 B). Nasale usually with five teeth, median tooth very small (Figure 10 C), sometimes absent, then nasale with four teeth. Epistomal lobes projecting about as far as nasale, right lobe with numerous short spine-like cuticular projections on inner margin; left lobe with dense, fine spine-like cuticular projections on inner margin (Figure 10 C). Antenna. Antennomere 2 covered with fine hair-like cuticular spines on ventral and inner surfaces (Figure 11 A). Antennomere 2 about 0.6 times as long as antennomere 1. Abdomen. Segment 1 with three transverse rows of tubercles behind sclerites (Figure 10 E); first row with five tubercles on each side, size of the tubercles from median to lateral one: Large (L), Small (S), rather L, S, L; second row with four tubercles on each side, inner three more closely situated than outer one: S, L, rather L, L; third row with three large tubercles on each side, outer one projecting laterally. Arrangement of tubercles of segments 2 to 5 similar to that of segment 1 but the tubercles of first and second transverse rows somewhat larger than those in segment 1: L, rather S, L, rather L, L in first row; rather L, L, rather L, L in second row. Segment 6 similar to segments 1 to 5 but tubercles somewhat smaller than those on segments 1 to 5: rather L, S, rather L, rather L, L in first row; rather S, rather L, rather S, L in second row. Segment 7 with three transverse rows of tubercles, first row with three tubercles on each side: rather L, S, L, lateral two more closely located; second row with three tubercles: S, rather L, L, median two more closely situated; third row with two tubercles on each side, outer one projecting laterally. Description of general morphology – second instar Slide preparations of two specimens were examined. Similar to third instar, more weakly sclerotized than in third instar. Head. Antenna moderately long, rather slender. Antennomere 2 about 0.7 times as long as Antennomere 1. Abdomen. Abdominal transverse rows of tubercles smaller than in third instar. Description of chaetotaxy of head – second instar Frontale. Lateral part bearing numerous rather short secondary setae, behind FR 4 – 6 sensilla (e. g. Figure 9 B). Each epistomal lobe with a group of seven moderately long, stout setae (gFR 2), inner three slightly shorter than outer ones. Parietale. Bearing many secondary sensilla, on dorsal and lateral areas (e. g. Figure 9 B). Mandible. With several small secondary setae on lateral part; base of mandible with five rather short secondary setae (e. g. Figure 11 B, C). Maxilla. Stipes with 13 – 14 long secondary setae on outer margin; one of them very long, close to MX 4 – 6 (e. g. Figure 11 D, E). Labium. Mentum with six to eight stout secondary setae in each anterolateral corner (e. g. Figure 11 F, G). Description of chaetotaxy of head – third instar Frontale. Each epistomal lobe with a group of seven to nine moderately long, stout setae (gFR 2), median three slightly shorter than lateral ones (Figure 10 C). Parietale. Bearing numerous, rather short secondary sensilla, on dorsal and lateral areas (e. g. Figure 9 A, B). Mandible (Figure 11 B, C). with several small secondary setae on lateral part; basal part of mandible with five rather short secondary setae, three close to primary cranial articulations of mandibles. Maxilla. Stipes with 11 long secondary setae on outer margin (Figure 11 D, E). Labium. Mentum with 10 – 11 stout secondary setae on each anterolateral corner (Figure 11 F, G). Habitat Lotic water (Figure 13 B). Larvae were found in leaf packs in the banks of a stream. Identification The larval specimens were collected from a mountain stream of near the top of Phou (Mount) Samsoun, northern Laos. The first author surveyed the locality for about one week and was able to collect only one species of Sperchopsini, i. e. H. uncinata. Therefore, we identified the larvae as H. uncinata. Instars were identified by sorting larvae according to the size of their head capsule and comparing the size of their head capsule with those of H. lacustris, which larvae as well as adults are almost of the same size. Conclusion Morphological comparison of allied genera of Hydrocassis In this section, we compare the larval morphology among genera of Sperchopsini based on our results and published data (Table 3). Larva of Cylomissus remains Notes: AU, Australasia; NA, Nearctic; NT, Neotropical; NZ, New Zealand; OR, Oriental; PA, Palaearctic. See Table 1 for references. unknown. The larvae of all genera are similar to each other in most characters, the only exception is the genus Anticura, which differs from all remaining Sperchopsini genera in the following characters: (1) nasale with two teeth; (2) inner surface of stipes with numerous stout, rather short setae; (3) dorsal sclerite of abdominal segment 8 divided into two sclerites. On the other hand, larvae of Hydrocassis are most similar to the larvae of the genus Sperchopsis and may only be distinguished by the number of setae on inner face of stipes (five in Hydrocassis, seven to eight in Sperchopsis). In contrast, the genus Hydrocassis is easily distinguishable from Ametor by the larval morphology, although Schödl and Ji (1995) indicated a close relationship between these genera and pointed out that only the adult character clearly distinguishes the genus Hydrocassis from Ametor, i. e. the position of the corona of the aedeagus. The larva of Hydrocassis is clearly distinguishable from that of Ametor by the following characters: (1) epistomal lobes with stout setae; (2) clypeolabrum asymmetrical; (3) frontal lines not fused at base. However, all information on larval stages of Ametor are based on the widely distributed Ametor scabrosus (Horn, 1873), which is easily distinguishable from the species of Hydrocassis by adult morphology. More extensive research on the larvae of Ametor is, therefore, necessary to solve the relationships of Hydrocassis and Ametor and confirm their separate generic states. Larval morphology within Hydrocassis Schödl and Ji (1995) subdivided the genus Hydrocassis into three species groups based on one adult morphological character: the shape of the parameres. The Hydrocassis species treated in the present paper belong to two of these species groups: H. lacustris and H. jengi into the H. scapulata group, H. uncinata into the H. scaphoides group. Larval morphology does not provide good characters to distinguish both species groups. The only character in which the species groups differ are the projections of abdominal segments: the projections are larger and stronger in H. uncinata than in H. jengi and H. lacustris (Figure 1). However, the size and shape of these projections are more or less continuous quantitative characters and their use as diagnostic is therefore limited. Moreover, there are no good characters which clearly separate the Hydrocassis species treated in this paper from each other. Of all studied characters, only the distribution and the size of tubercles on abdominal segments show slight differences among Hydrocassis species (Figures 4 E, 6 E, 10 E) and this character may therefore be useful for species identification and phylogenetic studies. The examination of more materials would be necessary to evaluate the significance of this character and confirm the homology of tubercles not only in Hydrocassis, but also in other genera of Sperchopsini.	en	Minoshima, Yûsuke, Hayashi, Masakazu (2011): Larval morphology of the genus Hydrocassis Fairmaire (Coleoptera: Hydrophilidae). Journal of Natural History 45 (45 - 46): 2757-2784, DOI: 10.1080/00222933.2011.602805, URL: http://dx.doi.org/10.1080/00222933.2011.602805
