Agraphydrus attenuatus Hansen, 1999

Komarek, Albrecht & Hebauer, Franz, 2018, Taxonomic revision of Agraphydrus Régimbart, 1903 I. China and Taiwan (Coleoptera: Hydrophilidae: Acidocerinae), Zootaxa 4452 (1), pp. 1-101 : 23-34

Agraphydrus attenuatus Hansen, 1999

(Figs. 5, 68, 87, 129)

Megagraphydrus attenuatus Hansen 1999: 141 .

Agraphydrus attenuatus ( Hansen, 1999) : Minoshima, Komarek & Ôhara 2015: 15.

Type locality. Vietnam, Vĩnh Phúc Province, Tam Ɖào.

Type material examined. Holotype Ƌ ( NMW): “N Vietnam, Tam Dao (2) \ 1.̄ 8.6.1996 \ leg. Dembicky \ & Pacholatko | Holotype \ Megagraphydrus \ attenuatus \ M. Hansen”. Paratypes: 24 exs. ( NMW, ZMUC): same sampling data.

Additional material examined. CHINA: Yünnan: 5 exs. ( NMW): CWBS 354 ; 7 exs. (NMW): CWBS 357; 3 exs. (NMW): CWBS 359; 10 exs. (NMW): CWBS 360; 1 ex. (NMW): CWBS 365; 1 ♀ (NMW): CWBS 367; 6 exs. (NMW): CWBS 371; 1 Ƌ (NMW): CWBS 373; 2 exs. (NMW): CWBS 377; 3 exs. (NMW): CWBS 379; 1 ex. (NMW): CWBS 390.

Differential diagnosis. This species belongs to the group with nine to ten rows of coarse elytral punctures, together with A. insidiator , A. politus , A. jaechi ( Hansen, 1999) , A. regularis ( Hansen, 1999) and A. siamensis ( Hansen, 1999) . Distinguished from these species by features of aedeagus. It differs from A. insidiator and A. politus by nine-segmented antennae, differently shaped maxillary palpi (palpomere 2 strongly widening), equal rows of coarse punctures on elytra ( A. insidiator and A. politus with alternating primary and secondary rows), and larger area of metafemoral pubescence. It differs from A. jaechi by maxillary palpi (palpomere 2 strongly widening towards apex, palpomere 4 shorter than palpomere 3), and features of aedeagus (apex of parameres acuminated), from A. regularis and A. siamensis by body shape (elytra attenuating posterior to midlength), from A. regularis by basal position of corona, from A. siamensis by parameres without incisions on mesal margins and apex of median lobe not reaching apex of parameres.

Description. Total length: 3.4̄ 4.8 mm; elytral width: 1.7̄ 2.4 mm; E.I.: 1.4, P.I.: 2.1̄2.2, elytra 2.9̄3.2× as long as pronotum. Habitus broad, elytra weakly attenuating posterior to midlength, moderately convex dorsally.

Coloration. Labrum and clypeus dark rufous to black with indistinct, undefined brighter rufous lateral margins about as wide as diameter of eye; frons black; maxillary palpi unicolored yellow; pronotum rufous to almost black with brighter yellowish to rufous margins; elytra black; ventrites and legs black; femora with rufous brown distal portions.

Head. Clypeus with distinctly, evenly excised anterior margin; C.I.: 3.3, lateral length ratio clypeus/eyes = 2.3; microsculpture absent; ground punctures moderately fine, distinctly impressed, interspaces 1̄2× as wide as punctures; systematic punctures moderately distinct, irregularly distributed among punctation on clypeus, present on frons posterior to frontoclypeal suture. Eyes small, not protruding, anterior edge impressed by posterior projection of clypeus, ventral portion of eye larger than dorsal part. Antennae with nine antennomeres. Maxillary palpi (Fig. 68) moderately slender, palpomere 2 strongly club-shaped, 1.1× as long as pronotum in midline, as long as maximum width of clypeus; length ratio palpomere 4:3 = 0.9, palpomere 4 slightly asymmetrical. Mentum with some fine punctures and distinct wrinkles on lateral portions.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct, some coarse punctures loosely distributed between long arcuate row in anterior corner and densely arranged cluster in midlength of lateral margin. Elytral ground punctation as on head and pronotum; ten distinct rows of coarse punctures present; few coarse punctures distributed within interserial spaces, punctures in mesal rows distinctly finer, less strongly impressed, lateral rows completely unordered. Mesoventrite with distinct, low, semilunar, transversal projection, directed ventrad with two closely aggregated ridges not recognisable by 100× amplification (visible in SEM: Minoshima et al. 2015); long, narrow, low, median carina present posterior to transversal ridges, extending between metacoxae.

Legs (Fig. 87). Pubescence present on proximal 2/3 of profemur with slightly oblique hairline, on proximal 3/4 of meso-and metafemur with straight hairlines.

Abdomen. Ventrite 5 with very shallow apical emargination, ca. 6̄8 µm deep.

Aedeagus (Fig. 129). Length: 0.53̄ 0.61 mm. Phallobase very short, shorter than wide; margins abruptly bending towards wide, bluntly rounded manubrium; border between pigmented and unpigmented portion of ventral face reaching proximal third. Parameres very narrow, 4× as long as basal lobe, with weakly, evenly curving margins; apex straight, very narrowly rounded; base weakly extending into phallobase; ventral face distinctly wider than dorsal face in distal half, with right and left lobe almost meeting in midline. Median lobe distinctly wider and slightly longer than parameres, apex projecting above apex of parameres; lateral margins evenly narrowing towards apex; corona large, in basal position; basal apophyses very long, distinctly bending laterad at base, extending to proximal third of phallobase.

Ecology. Collected between 600 and 1100 m a.s.l. in rivers, streams, and ponds in shrubs, cultivated land, degraded and primary forests.

Distribution. Vietnam (Vĩnh Phúc Prov.), China (Yünnan), Laos (Houa Phan Prov.: Minoshima et al. 2015).

Agraphydrus audax sp. n.

(Figs. 6, 88, 130)

Type locality. China, Hunan Prov., Xiangxi Prefecture; Dayong County; Zhangjiajie Forest National Park , Suoxiyü Nature Reserve , Wulingyüan section, 30 km N Dayong City ( CWBS 25 ).

Type material: Holotype Ƌ ( CASS): “ China, NW Hunan 1993 \ Wulingyuan, N Dayong \ Suoxiyu, 31.10., 450 m, leg L. Ji (6)” . Paratypes: CHINA: Hunan: 1 ♀ ( NMW): same sampling data, leg. Schillhammer “6”; 1 ex. ( NMW): NW-Hunan, Wulingyuan, N Dayong, Zangjiajie [National Park], 500 m a.s.l., 30.X.1993 , leg. L. Ji “3”; Guizhou: 1 Ƌ ( NMW): CWBS 445 ; Hubei: 2 exs. ( NMW): CWBS 546 ; Shaanxi: 1 ex. ( NMW): CWBS 311 ; Sichuan: 2 ƋƋ ( NMW): CWBS 218 ; 11 exs. (NMW): CWBS 220; 3 exs. (NMW): CWBS 222; 3 ♀♀ (NMW): CWBS 228; 1 ex. (NMW): CWBS 229; 11 exs. (NMW): CWBS 232; 1 ♀ (NMW): CWBS 233; 2 exs. (NMW): CWBS 234; 3 exs. (NMW): CWBS 235; 1 ex. (NMW): CWBS 236; 3 exs. (NMW): CWBS 238.

Differential diagnosis. This species belongs to the group of species with reduced chagrination on anterior margin of clypeus, unicolored yellow maxillary palpomeres, and dark brown to black clypeus, together with A. connexus , A. forcipatus , A. globipenis , A. narusei ( Satô, 1960) , A. ogatai Minoshima, 2016 , and A. setifer . It shares large size with A. setifer (total body length A. setifer : 2.3̄ 2.5 mm; all other species less than 2.3 mm). It shares cylindrical, narrow body and coarse, dense ground punctation on pronotum and elytra, with interspaces not larger than punctures, with A. narusei , in contrast to all other species mentioned. It differs from A. narusei by larger size and features of aedeagus (apex of parameres inflated), similar to aedeagus of A. arduus and A. igneus ; differs from these two species by reduced clypeal microsculpture and absence of anterolateral pronotal chagrination, from A. arduus also by stronger elytral ground punctation. It shares similar aedeagus also with A. kempi ( Orchymont, 1922) from Nepal and northern India, differing from this species by distinctly stronger pronotal and elytral ground punctation and by larger size.

Description. Total length: 2.6̄3.0 mm; elytral width: 1.7̄ 1.9 mm; E.I.: 1.4, P.I.: 2.2, elytra 3.1× as long as pronotum. Habitus moderately wide, elytra almost parallel-shaped, moderately convex dorsally.

Coloration. Labrum, clypeus, and frons black; clypeus with narrow rufous lateral margins, smaller than width of eye in most cases, rarely as wide as eye; maxillary palpi unicolored yellow; pronotum and elytra black with undefined, narrow, yellow lateral margins; ventrites black; legs and epipleura rufous.

Head. Clypeus with distinctly, evenly excised anterior margin; C.I.: 3.4, lateral length ratio clypeus/eyes = 1.7̄1.9; microreticulation present at lateral and anterior clypeal margins, but absent from very narrow median area at anterior margin; ground punctures coarse, interspaces as wide as punctures; systematic punctures distinct. Eyes large, but not protruding. Antennae with nine antennomeres. Maxillary palpi slender, 1.3× as long as pronotum in midline, 1.1× as long as maximum width of clypeus, length ratio palpomere 4:3 = 1.3, palpomere 4 asymmetrical. Mentum with coarse punctures laterally, partly confluent, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on head and pronotum; systematic punctures distinct, arranged in four rows, number of punctures strongly reduced in mesal rows, not reaching anterior margin. Mesoventrite with mesal bulge.

Legs (Fig. 88). Pubescence present on proximal 2/3 of profemur, on proximal 3/4 of meso- and metafemur; hairlines oblique on profemur, straight on meso-and metafemur.

Abdomen. Ventrite 5 with shallow apical emargination.

Aedeagus (Fig. 130). Length: 0.40 mm. Phallobase slightly shorter than parameres, slightly longer than wide; margins abruptly bending towards short, triangular manubrium; border between pigmented and unpigmented portion of ventral face reaching midlength. Parameres wide at base, strongly narrowing to subapical constriction; margins distinctly sigmoid; apex strongly inflated, with very thin cuticle; base of dorsal face reaching slightly into phallobase; ventral face much shorter and wider than dorsal face, with right and left lobe almost meeting in midline. Median lobe widest in midlength, bottle-shaped; margins evenly narrowing from midlength to bluntly rounded apex, not reaching apex of parameres; corona located in midlength; basal apophyses short, blunt, weakly separated, extending almost to midlength of phallobase.

Ecology. Collected between 600 and 1600 m a.s.l., in cold, fast flowing rivers with pebbles and stones, partly with aquatic vegetation or leaf packs, in streams near rice fields or flowing through other agricultural area, in slightly polluted streams in secondary forests, in a shallow water pool with sand, grass and mud at bank, in slowly flowing rivers with gravel, boulders and sand.

Distribution. China (Guizhou, Hubei, Hunan, Shaanxi, Sichuan).

Etymology. audax (Latin) = brave, audacious. The name alludes to the “audacious choice” of the species living in cold and fast flowing water.

Agraphydrus calvus sp. n.

(Figs. 7, 48, 89, 131)

Type locality. China, Hong Kong Admin. Reg., New Territories, Tai Mo Shan Country Park, SW Tai Po New Town, Lam Tsuen River ( CWBS 6).

Type material. Holotype Ƌ ( NMW): “ HONG KONG (5) 1992 \ N.T. - Lam Tsuen Riv. \ 25.VI. leg. Jäch ” [aedeagus mounted on separate card] . Paratypes: CHINA : Hong Kong: 1 ex. ( NMW): same sampling data; 1 ex. ( NMW): same locality, but 25.VI.1992 , leg. M. Jäch “5”; 4 exs. ( NMW): N.T., 3 km N Tai Po , 25.VI.1992 , M. Jäch “2”; 1 Ƌ ( NMW): N.T., Tai Po Kau Sp [ecial] Area , forest stream, 13.I.1997 , leg. W.D. Shepard “WDS-A-1248”; Guangdong: 1 ex. (NMW): CWBS 449; 1 ex. (NMW): CWBS 450; 2 exs. (NMW): CWBS 453; 15 exs. (NMW): CWBS 454; 2 exs. (NMW): CWBS 455; 1 ex. (NMW): CWBS 465; 2 exs. (NMW): CWBS 496; 1 Ƌ ( NMP): Guangdong Prov., W of Qixing, Heishiding Nature Reserve, 23°27.9'N, 111°54.3'E, 190̄ 260 m a.s.l., “small stream in primary lowland forest, among gravel and in accumulations of leaves”, 1.̄ 3.V.2011 , leg. Fikáček & Hájek “MF16”; Guangxi: 7 exs. ( NHM, ZMUC) : Guangxi, Guilin, Yaoshan , 24.̄ 25.IX.1980 , leg. P.M. Hammond, “B.M. 1980̄491”; Jiangxi: 54 exs. ( NMP, NMW) : Jiangxi Prov., Jinggangshan Mts. Shuangxikou (river valley), 26°31.4'N 114°11.3'E, 411 m a.s.l., “exposed wet rocks with algae, moss, and fallen leaves at side of

stony river”, 24.IV.2011, leg. M. Fikáček, J. Hájek, F.-L. Jia & Song, “MF02”; 1 Ƌ ( NMP): same locality data, but “sifting moist leaf litter in sparse forest along stony river”; 3 exs. ( NMP): Jiangxi Prov., Jinggangshan Mts., Baiyinhu env., 26°36.8'N 114°11.1'E, 800 m a.s.l., “drying-up stream in stony bed, night collecting in isolated pools in stream, on wet rocks with algae”, 23̄ 29.IV.2011, leg. M. Fikáček, J. Hájek & Kubeček “MF01”; 3 exs. ( NMP): Jiangxi Prov., Jinggangshan Mts., Jinggangshan Zhufeng, 26°32.0'N 114°08.6'E, 805 m a.s.l., “partly exposed wet rock with moss and fallen decaying leaves, beetles hiding mostly in moss, pyretroid spraying”, 29.IV.2011, leg. M. Fikáček, J. Hájek & Kubeček “MF14”; 12 exs. ( NMP): Jiangxi Prov., Jinggangshan Mts., Xiping, 26°33.7'N, 114°12.2'E, 915 m a.s.l., “small stream flowing from forest to rice fields”, 24.IV.2011, leg. M. Fikáček, J. Hájek, F.-L. Jia & Song, “MF04”.

Differential diagnosis. This species belongs to the group of species with anteriorly abbreviated mesal rows of systematic punctures on elytra, absence of clypeal microsculpture, and reduced metafemoral pubescence, together with A. geminus ( Orchymont, 1932) , A. indicus ( Orchymont, 1932) , A. longipalpus , and A. reductus . It shares absence of emargination on abdominal ventrite 5 and eight-segmented antennae with A. geminus , A. indicus , and A. reductus ; comparatively small eyes with A. geminus and A. reductus ; small size (less than 2.0 mm body length) with A. reductus and with some small individuals of A. indicus ; apical infuscation of palpomere 4 and similar aedeagus (including shield-like structure with triangular apical incision on median lobe) with A. indicus , differing by shorter basal lobe.

Description. Total length: 1.8̄ 1.9 mm; elytral width: 0.9̄1.0 mm; E.I.: 1.1̄1.2, P.I.: 2.1̄2.2, elytra 2.8̄2.9× as long as pronotum. Habitus broad, evenly oval, moderately convex dorsally.

Coloration. Labrum, clypeus, and frons black, brighter areas absent; maxillary palpi unicolored yellow or palpomere 4 with indistinct apical infuscation; pronotum dark brown or black with indistinct, undefined, narrow, yellow lateral margins and in some cases also with narrow yellow anterior margins; elytra dark brown or black; ventrites black; legs black, distal portions of femora and tibiae dark brown.

Head (Fig. 48). Clypeus with distinctly, evenly excised anterior margin; C.I.: 4.6, lateral length ratio clypeus/ eyes = 2.0; microsculpture absent; punctures fine, interspaces 1̄2× as wide as punctures; systematic punctures distinct. Eyes small, not protruding. Antennae with eight antennomeres. Maxillary palpi moderately slender, 0.9× as long as pronotum in midline, 0.8× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.3, palpomere 4 almost symmetrical. Mentum with some fine punctures, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on pronotum or slightly coarser and with denser distribution; systematic punctures indistinct, arranged in four rows, mesal rows with reduced number of punctures, not reaching anterior margin. Mesoventrite with distinct mesal bulge, abruptly sloping, with very low horizontal ridge posteriorly.

Legs (Fig. 89). Pubescence present on proximal 2/3 of profemur with oblique hairline, on proximal half of mesofemur with vertical hairline; metafemur without pubescence, some setae present on anterior margin.

Abdomen. Ventrite 5 apically weakly sclerotized, emargination absent.

Aedeagus (Fig. 131). Length: 0.29 mm. Phallobase less than half as long as parameres, abruptly bending towards distinct manubrium; border between pigmented and unpigmented portion of ventral face almost reaching manubrium in midline. Parameres widest in midlength, margins slightly sigmoid; apical region delicate, apex narrowly rounded, curving mesad; dorsal face reaching midlength of phallobase. Median lobe finger-shaped, with almost parallel-sided margins; apex blunt, almost reaching apex of parameres; ventral face slightly shorter and wider than dorsal face; corona located distally to midlength; shield-shaped structure, about as wide and about half as long as dorsal face, with distinctly excised apical margin, present in basal half, arising from base of median lobe; basal apophyses short, inclining laterad, extending to midlength of phallobase.

Ecology. Collected between sea level and 915 m a.s.l., in streams flowing through primary and degraded forests, through bamboo forests; among gravel and in accumulations of leaves, on exposed wet rocks with algae, in moss and leaves; in isolated pools of drying-up streams; on hygropetric rocks near waterfall.

Distribution. China (Guangdong, Guizhou, Hong Kong, Jiangxi).

Etymology. calvus (Lat.) = bare. The name refers to the absence of pubescence on the metafemur.

Agraphydrus cantonensis sp. n.

(Figs. 8, 90, 132)

Type locality. China, Guangdong Prov., Zhaoqing Pref., Fengkai County, ca. 50 km E of Fengkai, ca. 5 km W of Qixing, Heishiding Nature Reserve , 23°27'04"N 111°53'53"E ( CBWS 457 ) .

Type material. Holotype Ƌ ( CASS): “ CHINA: Guangdong Prov. \ 50 km E Fengkai \ 23°27'04"N 111°53'53"E \ 1.11.2001, ca . 300–400 m \ Jäch & Komarek ( CWBS 457 )”. Paratypes: CHINA: Guangdong: 2 ƋƋ, 2 ♀♀ ( NMW): same sampling data; 4 exs. ( NMW, ZUG): Guangdong Prov, Zhaoqing, Heishiding, 4.̄ 6.X.2013, leg. Fenglong Jia, Yue Jia, Bingjie Chen, Renchao Lin, Weilin Xu [labels in Chinese, translated by Si-Pei Liu].

Differential diagnosis. This species belongs to the group of species with reduced clypeal chagrination and unicolored palpomeres, together with A. audax , A. conicus , A. connexus , A. contractus , A. forcipatus , A. globipenis , and A. setifer . It differs from these species by yellow (versus largely dark brown or black) pronotum, and by features of aedeagus (with very short basal lobe); differs from A. connexus also by yellow clypeus (black in A. connexus ).

Description. Total length: 1.7̄ 1.9 mm; elytral width: 0.9 mm; E.I.: 1.2, P.I.: 2.0̄2.1, elytra 2.6× as long as pronotum. Habitus broad, evenly oval, strongly convex dorsally.

Coloration. Labrum and clypeus yellow; frons dark brown; maxillary palpi unicolored yellow; pronotum yellow; elytra dark brown; ventrites dark brown to black; legs dark brown.

Head. Clypeus with distinctly, evenly excised anterior margin, C.I.: 3.3, lateral length ratio clypeus/eyes = 3.0; clypeus narrowly microreticulated on lateral margin, and very narrow, indistinct microreticulation present along anterior edge; ground punctures fine, shallow, interspaces 2̄3× as wide as punctures; systematic punctures indistinct. Eyes small, not protruding. Antennae with eight antennomeres. Maxillary palpi moderately slender, as long as pronotum in midline, 0.8× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.2, palpomere 4 symmetrical. Mentum with very fine, very widely spaced punctures, without microsculpture.

Thorax. Pronotal ground punctation very fine, interspaces 2× as wide as punctures; systematic punctures moderately distinct. Elytral ground punctation fine, slightly stronger than on pronotum, shallow, interspaces 1̄2× as wide as punctures; systematic punctures indistinct, arranged in four rows, mesal rows with reduced number of punctures, not reaching anterior margin. Mesoventrite with low mesal bulge.

Legs (Fig. 90). Pubescence present on proximal 3/4 of femora; hairlines oblique.

Abdomen. Ventrite 5 with shallow apical emargination.

Aedeagus (Fig. 132). Length: 0.23 mm; cuticle very delicate, indistinctly pigmented. Phallobase less than half as long as parameres, about as long as wide, abruptly bending towards distinct manubrium; border between pigmented and unpigmented portion of ventral face indistinct, reaching proximal third of phallobase in midline. Parameres moderately wide; margins sigmoid, mesal margin with wide bulge in midlength; apex bluntly rounded, not inflated; base of dorsal face reaching midlength of phallobase; ventral face slightly shorter and distinctly wider. Median lobe not reaching apex of parameres; dorsal face bottle-shaped, wide basally, bending in midlength to narrow distal half; apex bluntly rounded, with indistinct dent; corona large, located in distal third; basal apophyses long, extending to distal third of phallobase.

Ecology. Collected between 300 and 400 m a.s.l. in pools near streams flowing through dense primary forest.

Distribution. China: Guangdong.

Etymology. The name refers to “Canton” a former name of the Province Guangdong in China where the type specimens were collected.

Agraphydrus chinensis sp. n.

(Figs. 9, 49, 91, 133)

Type locality. China, Fujian Prov., Jianyuan Prefecture, Chong’an City Region, Chong’an Wuyi Shan ( CWBS 240).

Type material. Holotype Ƌ ( CASS): “ China: Fujian \ Chong'an Wuyi Shan \ 15./18.1.[19]97 Ji / Wang [ CWBS 240 ]” [handwritten] . Paratypes: CHINA: Fujian: 1 Ƌ, 3 E ( NMW): CWBS 240 ; 1 ♀ (NMW): CWBS 241; 1 Ƌ

(NMW): CWBS 243. Anhui: 3 ƋƋ ( NMW): CWBS 284 ; Zhejiang: 14 exs. ( NMW): CWBS 412 ; 1 Ƌ (NMW): CWBS 430.

Differential diagnosis. This species belongs to the group of species with four rows of systematic punctures, unsculptured clypeus, nine-segmented antennae, unicolored palpomeres, and wide-stretched metafemoral pubescence, together with A. fikaceki , A. masatakai , and A. splendens . It differs from A. fikaceki by indistinct, less numerous, systematic punctures; from A. splendens and A. masatakai by smaller eyes, less wide clypeus, presence of mesoventral ridge, and absence of apical emargination on abdominal ventrite 5. It shares absence of emargination on ventrite 5 and very similar aedeagus with A. fujianensis , differing by number of antennomeres ( A. fujianensis with eight-segmented antennae), and presence of mesoventral ridge (median carina present in A. fujianensis ). Similar shape of parameres is present in A. yunnanensis , a species with differently colored pronotum, coarser ground punctation, and eight-segmented antennae.

Description. Total length: 2.2 mm; elytral width: 1.1 mm; E.I.: 1.2̄1.3, P.I.: 2.1̄2.2, elytra 2.7× as long as pronotum. Habitus broad, evenly oval, moderately convex dorsally.

Coloration. Labrum, clypeus and frons black, lateral margins of clypeus with undefined dark yellow areas; maxillary palpi unicolored yellow; pronotum dark brown with decreasing intensity of coloration towards dark yellow margins; elytra unicolored rufous brown; ventrites dark brown; legs lighter brown.

Head (Fig. 49). Clypeus with distinctly, evenly excised anterior margin, C.I.: 3.8, lateral length ratio clypeus/ eyes = 3.2; microsculpture absent; ground punctures fine, interspaces about 2× as wide as punctures; systematic punctures distinct. Eyes small, not protruding, distinctly oblong. Antennae with nine antennomeres, antennomere 4 minute. Maxillary palpi slender, 1.1̄1.2× as long as pronotum in midline, as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.2̄1.4, palpomere 4 slightly asymmetrical. Mentum with fine, evenly distributed punctures, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on pronotum or slightly stronger; systematic punctures indistinct, arranged in four rows, mesal rows with strongly reduced number of punctures, present in posterior and anterior half, not reaching anterior margin. Mesoventrite with low, horizontal, slightly arcuate ridge, and low, short, median carina posterior to ridge.

Legs (Fig. 91). Pubescence present on proximal 2/3 of profemur, on proximal 3/4 of meso- and metafemur; hairlines straight to curved.

Abdomen. Ventrite 5 weakly sclerotized apically, truncate, emargination absent.

Aedeagus (Fig. 133). Length: 0.28̄ 0.34 mm. Phallobase slightly shorter than parameres, almost as wide as long, abruptly bending to triangular manubrium; border between pigmented and unpigmented portion of ventral face distinct, almost reaching manubrium in midline. Parameres wide in proximal half, mesal margin abruptly narrowing to distal half in midlength; lateral margin slightly sigmoid; apex bluntly rounded, not inflated, asymmetrical; base weakly extending into phallobase mesally; ventral face very indistinct. Median lobe fingershaped, narrow; apex of dorsal face almost reaching apex of parameres; ventral face half as long as dorsal face and distinctly wider; corona large, in basal position; basal apophyses moderately long, widely separated, extending to distal third of phallobase.

Remarks. Specimens from Anhui differ from individuals from Fujian by minor size of the yellow preocular areas.

Ecology. Collected between 200 and 500 m a.s.l. in residual and springfed pools, partly with plant debris, and in a small stream with rocks, fast flowing through Cunninghamia forest.

Distribution. China (Anhui, Fujian, Zhejiang).

Etymology. The name refers to China where this species was collected.

Agraphydrus comes sp. n.

(Figs. 10, 92, 134)

Type locality. China, Hainan Prov., Ledong County, foot of Jianfeng Mountain , ca. 4 km E Jianfeng Town ( CWBS 204 ).

Type material. Holotype Ƌ ( CASS): “ CHINA: Hainan (204) \ 4 km E Jianfeng, 150 m \ Jianfeng Mt. 1996 \ 22.̄24.1., leg. Ji & Wang ” . Paratypes: CHINA: Hainan: 30 exs. ( NMW): same sampling data; 18 exs. ( NMW): CWBS 205 ; 1 Ƌ, 1 ♀ (NMW): CWBS 197; 2 ♀♀ (NMW): CWBS 202; 4 ♀♀ (NMW): CWBS 208.

Differential diagnosis. This species belongs to the group of species with apically infuscated maxillary palpomere 4 and absence of clypeal microsculpture, together with A. coomani , A. confusus , A. ishiharai ( Matsui, 1994) , A. jilanzhui and A. robustus (see also Remarks under A. coomani ). It differs from A. jilanzhui by yellow (versus black) pronotum, from A. robustus , A. ishiharai , and A. jilanzhui by absence of apical extension of parameres, and from all species by uniquely shaped parameres (acuminate, kinking in apical third); differing from A. coomani also by stronger pronotal and elytral ground punctation.

Description. Total length: 1.9̄ 2.3 mm; elytral width: 0.8̄ 1.1 mm; E.I.: 1.6, P.I.: 1.9, elytra 3.1× as long as pronotum. Habitus slender, elytra slightly widening posterior to midlength, weakly convex dorsally.

Coloration. Labrum, clypeus and frons black, clypeus with yellow preocular patches, about as wide as diameter of eye or smaller; maxillary palpi yellow, palpomere 4 with apical infuscation; pronotum with large, weakly defined, black central patch, reaching to level of eyes, attaining posterior margin, with large yellow lateral margins and narrow yellow anterior margin; elytra yellow; ventrites black; legs brown.

Head. Clypeus with distinctly, evenly excised anterior margin; C.I.: 2.9, lateral length ratio clypeus/eyes = 1.4; microsculpture absent; ground punctures fine, interspaces 2× as wide as punctures; systematic punctures moderately distinct. Eyes large, very slightly protruding. Antennae with nine antennomeres. Maxillary palpi slender, 1.1× as long as pronotum in midline, as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.4, palpomere 4 slightly asymmetrical. Mentum almost impunctate, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures moderately distinct. Elytral ground punctation as on head and pronotum; systematic punctures indistinct, arranged in four rows, row 1̄3 with strongly reduced number of punctures, not reaching anterior margin. Mesoventrite with mesal bulge.

Legs (Fig. 92). Pubescence present on proximal 2/3 of profemur, on proximal 3/4 of meso- and metafemur; hairline oblique on profemur, almost straight on meso- and metafemur.

Abdomen. Ventrite 5 with shallow apical emargination, 10̄15 µm deep.

Aedeagus (Fig. 134). Length: 0.40̄ 0.43 mm. Phallobase about as long as parameres, longer than wide, evenly bending proximad; delimited manubrium absent; border between pigmented and unpigmented portion of ventral face reaching almost proximal end of phallobase in midline. Parameres wide basally, with weakly curving margins, slightly kinking mesad in apical third, tapering to very narrowly rounded apex; base reaching distal fourth of phallobase. Median lobe moderately wide, finger-shaped; apex evenly rounded, not reaching apex of parameres; ventral face slightly wider apically than dorsal face; corona in apical position; basal apophyses moderately long, slightly inclining laterad, extending to distal fourth of phallobase.

Ecology. Collected between 60 and 800 m a.s.l. in streams flowing through primary and secondary forests, pastures, rice fields and shrubs.

Distribution. China (Hainan).

Etymology. comes (Lat.) = companion. The name refers to the fact that the species is found in company of A. coomani , and is used as noun in apposition.

Agraphydrus confusus sp. n.

(Figs. 11, 93, 135)

Type locality. China, Hong Kong Admin. Reg., Tai Po Kau Nature Reserve.

Type material. Holotype Ƌ ( NMW): “ HONG KONG Tai Po Kau [N.R.] \ 27.̄ 28.9.1983, leg. Dudgeon (upstr.)” . Paratypes: CHINA : Hong Kong : 9 exs. ( NMW): same sampling data; 3 exs. ( NMW) : same locality data, but “ 6.VII.1983 ”; 1 ex. ( NMW) : same locality data, but “6.̄ 7.VI.1984 ”; 11 exs. ( NMW) : same locality data, but “16.̄ 17.V.1984 ”; 1 ex. ( NMW) : same locality data, but “downstream, 16.̄ 18.V.1984 ”; 4 exs. ( NMW) : same locality data, but “downstream, 18.X.1983 ”; 1 ex. ( NMW) : same locality data, but “ 28.VII.1983 ”; Yünnan: 4 ƋƋ ( NMW): CWBS 361 ; Guizhou: 5 exs. ( NMW): CWBS 265 . VIETNAM: 6 exs. ( NME, NMW) : Vietnam, Lào Cai Prov., Sa Pa [ Town ], 250 km NW Hanoi, env. Hoang Lian Son Nat. Res. , 1250 m a.s.l., 21.̄ 23.VI.1998, leg. A. Napolov; 1 ex. ( NMW) : Vietnam, [Lào Cai Prov.], Hoang Lien Son , 1600 m a.s.l., 11.̄ 16.V.1990, leg. J. Horák.

Differential diagnosis. This species belongs to the group of species with apically infuscated maxillary palpomere 4 and absence of clypeal microsculpture, together with A. coomani , A. comes , A. ishiharai , A. jilanzhui and A. robustus (see also Remarks to A. coomani ); differing from A. jilanzhui by yellow (versus black) pronotum, from A. coomani by stronger pronotal and elytral ground punctation, and from all species by shape of parameres (apex strongly bending mesad).

Description. Total length: 1.9̄ 2.3 mm; elytral width: 0.9̄1.0 mm; E.I.: 1.5, P.I.: 1.9, elytra 3.0̄3.2× as long as pronotum. Habitus slender, elytra slightly widening posterior to midlength, weakly convex dorsally.

Coloration. Labrum, clypeus and frons black, clypeus with distinctly delimited, triangular preocular patches, about as wide as eye; maxillary palpi yellow, palpomere 4 with infuscation apically; pronotum yellow with distinct black central patch with variably wide extension, contacting posterior margin, reaching level of eyes laterally, with wide lateral yellow margins, and with narrow anterior yellow rim in most cases; elytra yellow; ventrites dark brown or black; legs yellowish brown.

Head. Clypeus with distinctly, evenly excised anterior margin, C.I.: 3.1, lateral length ratio clypeus/eyes = 1.6; microsculpture absent; ground punctures moderately distinct, interspaces 2× as wide as punctures or slightly wider; systematic punctures distinct. Eyes large, very slightly protruding. Antennae with nine antennomeres. Maxillary palpi slender, 1.1× as long as pronotum in midline, 1.0̄1.2× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.4, palpomere 4 slightly asymmetrical. Mentum with very fine, very widely spaced punctures, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on head and pronotum; systematic punctures distinct, arranged in four rows, mesal rows with strongly reduced number of punctures, not reaching anterior margin. Mesoventrite with mesal bulge.

Legs (Fig. 93). Pubescence present on proximal 2/3 of femora, slightly more extended on mesofemur; hairline slightly oblique on profemur, almost straight on meso- and metafemur.

Abdomen. Ventrite 5 with shallow apical emargination, 10̄12 µm deep.

Aedeagus (Fig. 135). Length: 0.39̄ 0.43 mm. Phallobase about as long as parameres, slightly longer than wide, evenly curving proximad; delimited manubrium absent; border between pigmented and unpigmented portion of ventral face indistinct, almost reaching proximal end of phallobase in midline. Parameres moderately wide at base, with sigmoid margins and subapical constriction; apex strongly bending mesad; base of dorsal face reaching distal third of phallobase. Median lobe moderately wide, finger-shaped; apex bluntly rounded, not reaching apex of parameres; ventral face very slightly wider and shorter than dorsal face; corona in apical position; a pair of styli present, arising from base of median lobe, not reaching its apex; basal apophyses moderately long, distinctly separated, extending to distal third of phallobase.

Ecology. Collected between 700 and 160 m a.s.l. in rivers flowing through agricultural land and degraded forest, and in a polluted pool with aquatic vegetation.

Distribution. China (Guizhou, Hong Kong, Yünnan), Vietnam (Lào Cai Prov.).

Etymology. confusus (Lat.) = confused. The name refers to the similarity with A. coomani , with which this species can easily be confused.

Agraphydrus conicus sp. n.

(Figs. 12, 50, 69, 94, 136)

Type locality. China, Jiangxi Prov., Jinggangshan Mountains, Jingzhushan , 26°31.0'N 114°05.9'E.

Type material. Holotype: ( NMP): “ CHINA: Jiangxi Prov. MF 06 \ Jinggangshan Mts. , Jingzhushan, 640 m \ 26°31.0'N, 114°05.9'E, 25.IV.2010 \ Fikáček, Hájek, Jia & Song” . Paratypes: CHINA: Jiangxi: 4 exs. ( NMP, NMW): same locality data, but “quickly flowing stony stream amid the bushy pastures, in gravel at the banks, in moss on the stones in small waterfalls”, and “in cow excrements on the forest clearing”; 4 exs. ( NMW): CWBS 306 ; 3 exs. (NMW): CWBS 513; 2 exs. (NMW): CWBS 517; Anhui: 13 exs. ( NMW): CWBS 287 ; 2 ♀♀ (NMW): CWBS 293; 1 ♀ (NMW): CWBS 284; Hunan: 1 ♀ ( NMW): CWBS 503 ; 6 exs. (NMW): CWBS 504; 1 ♀ (NMW): CWBS 521.

Differential diagnosis. This species belongs to the group of species with unicolored maxillary palpomeres, chagrination on lateral and anterior margins of clypeus, nine-segmented antennae, and dark brown to black pronotum, together with A. audax , A. connexus , A. contractus , A. forcipatus , A. globipenis , and A. setifer . It shares particular body shape (large pronotum, strongly attenuating elytra), small eyes (lateral length ratio clypeus/eyes = 3.5), and features of aedeagus, with A. contractus . It shares comparatively coarse pronotal and elytral ground punctation with A. contractus and A. audax . It differs from A. contractus by slightly finer ground punctation of head, pronotum, and elytra and by slightly more slender maxillary palpomeres. It differs from all species of Agraphydrus by features of aedeagus (median lobe bottle-shaped with distinctly notched apex, corona located in apical third, parameres not inflated, subapical constriction absent, manubrium spine-like).

Description. Total length: 2.0̄ 2.3 mm; elytral width: 1.1̄ 1.2 mm; E.I.: 1.1̄1.2, P.I.: 2.2̄2.3, elytra 2.5× as long as pronotum. Habitus broad, elytra distinctly attenuating posterior to midlength, strongly convex dorsally.

Coloration. Labrum, clypeus and frons black, preocular patches absent; maxillary palpi unicolored yellow; pronotum and elytra dark brown to black with narrow, undelimited yellow lateral margins; ventrites dark brown to black; legs lighter brown.

Head (Fig. 50). Clypeus with distinctly, evenly excised anterior margin; C.I.: 3.8, lateral length ratio clypeus/ eyes = 3.5; clypeus distinctly microreticulated at lateral and anterior margins; ground punctures moderately coarse, interspaces about as wide as punctures or slightly wider; systematic punctures distinct. Eyes small, not protruding. Antennae with nine antennomeres. Maxillary palpi (Fig. 69) slender, as long as pronotum in midline, 0.9× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.2, palpomere 4 slightly asymmetrical. Mentum with moderately coarse punctures in lateral third, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on head and pronotum; systematic punctures distinct, arranged in four rows, mesal rows with strongly reduced number of punctures, not reaching anterior margin, additional row present along lateral margins. Mesoventrite with very strong mesal bulge.

Legs (Fig. 94). Pubescence present on more than proximal half of femora with slightly oblique hairlines.

Abdomen. Ventrite 5 with shallow apical emargination.

Aedeagus (Fig. 136). Length: 0.42̄ 0.44 mm. Phallobase distinctly longer than parameres, longer than wide, evenly curving towards long, narrow, manubrium; border between pigmented and unpigmented portion of ventral lobe indistinct, reaching midlength in midline. Parameres almost equally wide at base and apex; margins weakly curved; apex blunt, not inflated, asymmetrical; base reaching distal third of phallobase. Median lobe bottle-shaped, moderately wide, parallel-sided in basal 3/4, abruptly narrowing in apical fourth; apex with distinct notch, reaching apex of parameres; corona located in apical third; basal apophyses short, extending to distal third of phallobase.

Ecology. Collected between 350 and 800 m a.s.l. in residual pools of partly dried out streams, partly with leaves, in streams flowing through rice terraces, vegetable and tea gardens, forests, and in mountain streams with sand, boulders, and flood debris.

Distribution. China (Anhui, Hunan, Jiangxi).

Etymology. conicus (Lat.) = cone-shaped. The name refers the cone-shaped elytra.

Agraphydrus connexus sp. n.

(Figs. 13, 14, 15, 95, 137)

Type locality. Malaysia, Pahang, Kuala Lipis [ Town ] surround.

Type material. Holotype Ƌ ( NMW): “West Malaysia, Pahang [state] \ Kuala Lipis surr., small \ stream, 12.4.1997, 60 m \ Balke & Hendrich leg.” . Paratypes: MALAYSIA: 1 Ƌ same sampling data; 1 Ƌ ( NMW): Johor [Segamat district], Bekok , path to waterfall, 50̄ 150 m a.s.l., 10.IV.1997, leg. M. Balke & L . Hendrich. CHINA: Hainan: 14 exs. ( NMW) : CWBS 182; 4 exs. (NMW): CWBS 188; 17 exs. (NMW): CWBS 193; 1 Ƌ (NMW): CWBS 194; 1 Ƌ (NMW): CWBS 202; 11 exs. (NMW): CWBS 204; 6 exs. (NMW): CWBS 205; 1 Ƌ, 2 ♀♀ (NMW): CWBS 207; 6 exs. (NMW): CWBS 208; 1 ♀ (NMW): CWBS 213; 2 exs. (NMW): CWBS 214; 6 exs. (NMW): CWBS 215. LAOS: 1 Ƌ ( NMW): Champasak Prov., ca. 50 km E Muang Paksong , 700 m a.s.l., 27.V.1996, leg. Schillhammer “9” . MYANMAR: 13 exs. ( NMW): Shan State, road Kalaw ̄ Thazi , km 26, 20°43.8'N 96°29.47'E, ca. 550 m a.s.l., 16.V.1999, leg. Schillhammer & Schuh “44” . NEPAL: 6 exs. ( MNS, NMW): [Mechi zone], Ilam District, 5 km N Sanishare, Siwalik Mts. , 270̄ 300 m a.s.l., 3.̄ 5.IV.1988, leg. W. Schawaller “308” . THAILAND: 1 Ƌ, 1 ♀ ( NMW): Phetchanbun Prov., Nam Nao NP, 24.XI.1995, leg. H. Zettel “22” ; 1 ♀ ( NMW): Phetchabun [Prov.], Nam Nao NP, Huai Ya Krua , 14.III.1994, leg. W. Shepard ; 1 Ƌ, 1 ♀ ( NMW): [Mae Hong Son Prov.], 12 km S Mae Hong Son [Town], Pha Bong , 12.XI.1995, leg. H. Zettel “13a” ; 1 ♀ ( NMW): Phrae [Prov.], 50 km NE Phrae [ Town ], 5 km SE B[an] Huai Kaet , 18.XI.1995, leg. H. Zettel “18a” ; 2 ♀♀

( NMW): [Chiang Mai Prov.] , Chiang Mai [City], Zoo , at light, 23.V. ̄ 1.VI.1988, leg. Malicky. VIETNAM: 2 ♂♂, 4 ♀♀ ( ISNB): N-Vietnam , Hoa Binh, Lac Tho , leg. de Cooman ; 1 Ƌ (EUM): Cao Bang [Prov.], “ Ban Khuoi Han ”, 230 m a.s.l., 30.IX.1994, leg. M. Satô.

Differential diagnosis. This species belongs to the group of species with almost entirely chagrinated clypeus and unicolored maxillary palpomere 4, together with A. arduus , A. connexus , A. gracilipalpis , A. igneus , A. narusei , A. ogatai , A. orientalis , A. reticuliceps , A. schoenmanni , and many individuals of A. umbrosus . It differs from A. gracilipalpis and A. reticuliceps by minor size and evenly oval body, from A. gracilipalpis also by distinctly finer pronotal and elytral ground punctation, from A. arduus and A. igneus by absence of microsculpture on anterior pronotal angles and by darker colored clypeus. Individuals with less extended clypeal chagrination are similar to A. forcipatus , A. audax , and A. setifer . It differs from these species by features of aedeagus; from A. audax and A. setifer also by minor size; from A. audax moreover by finer dorsal ground punctation. It differs from A. narusei and A. ogatai by evenly oval body and larger eyes. It shares with A. orientalis similar shape of parameres and median lobe (broadly rounded apex), differs by 9-segmented antennae. Distinguished from all species of Agraphydrus by distinct median connecting band between basis of parameres and median lobe.

Description. Total length: 1.9̄ 2.2 mm; elytral width: 0.8̄1.0 mm; E.I.: 1.3̄1.4, P.I.: 2.0̄2.1, elytra 2.9̄3.1× as long as pronotum. Habitus moderately broad, evenly oval, moderately convex dorsally.

Coloration very variable: Labrum, clypeus and frons black; clypeus with yellow preocular patches, as wide as eyes or smaller, weakly defined and indistinct in some cases, or restricted to lateral margins, or absent in some cases; maxillary palpi unicolored yellow; pronotum dark brown with variably sized, undefined, yellow margins, wider at lateral sides than anteriorly, or light brown with decreasing intensity towards yellow lateral margins, rarely pronotum unicolored yellow; elytra light to dark brown, lateral margins narrowly yellow with black or rarely dark brown sublateral band, wider anteriorly than in posterior half, very indistinct in some cases, sutural region narrowly black; ventrites black; legs dark brown to black.

Head. Clypeus with distinctly, evenly excised anterior margin; C.I.: 3.9, lateral length ratio clypeus/eyes = 1.4; clypeus with microreticulation on almost entire surface, absent only from small posterior area in most individuals, or microreticulation restricted to anterior half; ground punctures within microreticulated area obsolete, on frons fine, interspaces 2̄3× as large as punctures; systematic punctures distinct. Eyes large, but not protruding. Antennae with nine antennomeres. Maxillary palpi slender, 1.0̄1.1× as long as pronotum in midline, 0.9̄1.0× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.4̄1.5, palpomere 4 almost symmetrical. Mentum with few fine punctures laterally, without microsculpture.

Thorax. Pronotal ground punctation fine, as on frons; systematic punctures distinct. Elytral ground punctation fine, distributed as on pronotum; systematic punctures moderately distinct, arranged in four rows, mesal rows with strongly reduced number of punctures, not reaching anterior margin. Mesoventrite with mesal bulge.

Legs (Fig. 95). Pubescence present on proximal 2/3 of profemur and metafemur, on proximal 3/4 of mesofemur; hairlines slightly oblique on pro- and mesofemur, straight on metafemur.

Abdomen. Ventrite 5 with shallow to semicircular apical emargination.

Aedeagus (Fig. 127). Length: 0.25̄ 0.27 mm. Phallobase about as long as parameres, as long as wide, evenly curving towards conical manubrium; border between pigmented and unpigmented portion of ventral face reaching distal third. Parameres moderately wide, with slightly curving margins; apex delicate, bluntly rounded, slightly inflated, inclining mesad; base slightly extending into phallobase; right and left lobes of dorsal face connected with base of median lobe by distinct median band; ventral face very indistinct, shorter than dorsal face. Median lobe wider than one paramere basally; margins evenly converging to blunt apex, reaching apex of parameres; corona large, in subapical position; basal apophyses widely separated, moderately short, inclining laterad, extending to distal third of phallobase.

Remarks. The coloration of head, pronotum and elytra differs according to the geographical distribution. In most specimens from Hainan the preocular patches are absent, the yellow coloration on the margins of the pronotum are usually widely extended, the dark brown central patch is small, the black sublateral elytral band is distinct and the yellow lateral margin is very narrow or even absent. Specimens from Thailand have narrow preocular patches and a large dark brown pronotal coloration in most cases; the black elytral band is distinct or indistinct, a lateral yellow margin is present. In many individuals from Myanmar the lateral clypeal margins are very narrowly yellow, the pronotum is largely dark brown with narrow yellow margins, the elytra are very variable, but a narrow yellow lateral margin is present in almost all cases. The specimen from Laos is similar to the individuals from Myanmar, but the black sublateral elytral band is very indistinct. Specimens from Vietnam have distinct preocular patches, as wide as diameter of eyes, a very variably sized dark brown center of pronotum, rather light colored elytra, the black band is distinct or indistinct. Specimens from West Malaysia have distinct yellow preocular patches, a small dark brown center of pronotum (in one specimen the pronotum is unicolored yellow), very light colored elytra, and a black sublateral band is present (absent in one specimen). Individuals from Nepal have distinct preocular patches, the pronotum is light brown mesally with decreasing intensity of coloration towards the yellow lateral margins, the elytra are light colored, the elytral sublateral band is dark brown and very indistinct.

Ecology. Collected between sea level and 800 m a.s.l. in streams and rivers flowing through rice fields, rubber plantation, pastures, village gardens, shrubs, bamboo groves, and degraded forests; in mud, sand, gravel, between large boulders; in various kinds of pools; at light.

Distribution. China (Hainan), Laos, Malaysia, Myanmar, Thailand, Vietnam; Nepal.

Etymology. connexus (Lat.) = connected. The name refers to the connecting band between parameres and median lobe.

Agraphydrus contractus sp. n.

(Figs. 16, 51, 70, 96, 138)

Type locality. China, Fujian Prov., Jianyuan Prefecture; Yong’an City Region; ca. 20 km SE Yong’an City, 5 km SW Xiyang Village, Ziyungdong Shan ( CWBS 256 ).

Type material. Holotype Ƌ ( CASS): “ CHINA: FUJIAN, Yong’an \ 5 km SW Xiyang, 550 m \ Ziyungdong Shan, 25.1.1997 \ leg. Ji & Wang ( CWBS 256 )”. Paratypes : CHINA: Fujian: 4 exs. ( NMW): same sampling data; 3 exs. ( NMW): CWBS 243 ; 1 ex. ( NMW): CWBS 249 ; 1 Ƌ ( NMW): CWBS 250 ; 1 ex. ( NMW): CWBS 258 ; 8 exs. ( NMW): CWBS 259 ; 2 exs. ( NMW): CWBS 260 ; Guangdong: 1 Ƌ ( NMW): CWBS 496 ; 1 ♀ ( NMP): 30 km NE Shaoguan, Duanshi village, Danxiashan NP, 25°02.7'N 113°43.8'E, 125 m a.s.l., stream, pools, 4.̄ 5.V.2011, leg. J. Hájek.

Differential diagnosis. This species belongs to the group of species with unicolored maxillary palpomeres, reduced clypeal chagrination, and nine-segmented antennae, together with A. audax , A. connexus , A. conicus , A. forcipatus , A. globipenis , and A. setifer . It shares particular body shape (large pronotum, strongly attenuating elytra), black coloration, small eyes (lateral length ratio clypeus/eyes = 4.5), and features of aedeagus with A. conicus . It shares comparatively coarse pronotal and elytral punctation with A. conicus and A. audax . It differs from all species by features of aedeagus (median lobe wide with blunt apex, corona situated proximally to midlength, parameres inflated with distinct subapical constriction).

Description. Total length: 2.0̄ 2.2 mm; elytral width: 1.1̄ 1.2 mm; E.I.: 1.1, P.I.: 2.2, elytra 2.4× as long as pronotum. Habitus broad, elytra distinctly attenuating towards apex, moderately convex dorsally.

Coloration. Labrum, clypeus, and frons entirely black, preocular patches absent; maxillary palpi unicolored yellow; pronotum black with indistinctly delimited, narrow yellow lateral margins; elytra black with narrow yellow lateral margins; ventrites black; legs light brown.

Head (Fig. 51). Clypeus with distinctly, evenly excised anterior margin; C.I.: 3.8, lateral length ratio clypeus/ eyes = 4,5; microreticulation present at lateral edge and at anterior margin of clypeus, reduced or absent from a small area on mesal parts of anterior margin in some individuals; ground punctures coarse, interspaces about as wide as punctures; systematic punctures indistinct on antero-lateral angle of clypeus, distinct on frons posterior to fronto-clypeal suture. Eyes small, not protruding, distinctly oblong. Antennae with nine antennomeres, antennomere 4 minute. Maxillary palpi (Fig. 70) slender, 0.9× as long as pronotum in midline, 0.8× as long as maximum width of clypeus; length ratio palpomere 4:3 = 1.5̄1.6, palpomere 4 asymmetrical. Mentum with fine punctures on lateral portion, without microsculpture.

Thorax. Pronotal ground punctation as on head; systematic punctures distinct. Elytral ground punctation as on pronotum; systematic punctures indistinct, arranged in four rows, mesal rows with strongly reduced number of punctures, not reaching anterior margin. Mesoventrite with a very low, crescentic, horizontal ridge and a short median ridge posterior to ridge.

Legs (Fig. 96). Pubescence present on proximal 2/3 of profemur with oblique hairline, on proximal 3/4 of mesofemur with oblique hairline, on proximal 2/3 of metafemur with straight hairline.

Abdomen. Ventrite 5 with indistinct, shallow apical emargination.

Aedeagus (Fig. 138). Length: 0.37̄ 0.38 mm. Phallobase almost as long as parameres, abruptly bending towards distinctly delimited manubrium; border between pigmented and unpigmented portion of ventral face almost reaching manubrium in midline. Parameres wide basally, margins distinctly sigmoid, with subapical constriction; apical region very delicate; apex hemispherical; base reaching distal third of phallobase; mesal face wider and shorter than dorsal face. Median lobe wide; apex bluntly rounded, almost reaching apex of parameres; corona located proximal to midlength; basal apophyses short, slightly inclining laterad, extending to midlength of phallobase.

Ecology. Collected between 250 and 1000 m a.s.l. in streams flowing through forests and rice fields; in small springfed pool in plum tree plantation, in roadside and rock pools with sand, decaying organic matter, and gravel; often found in cold water.

Distribution. China (Fujian, Guangdong).

Etymology. contractus (Lat.) = contracted. The name alludes to the shape of the elytra which appear “contracted” apically.