Copelatus chinensis Régimbart, 1899: 298 Copelatus collocallosus Falkenström, 1932: 192 Copelatus collocallosus Falkenström, 1933: 14 Gschwendtner (1939: 40) A review of Copelatus Erichson, 1832 of Mainland China, with description of ten new species from the japonicus complex (Coleoptera: Dytiscidae: Copelatinae) Jiang, Zhuo-Yin Zhao, Shuang Yang, Zhen-Yu Jia, Feng-Long Hájek, Jiří Zootaxa 2022 2022-04-04 5124 3 251 295 Regimbart, 1899 Regimbart 1899 [151,609,1656,1684] Insecta Dytiscidae Copelatus Animalia Coleoptera 2 253 Arthropoda species chinensis  ( Figs 2–3, 31–32)      Copelatus chinensis Régimbart, 1899: 298.     Copelatus collocallosus Falkenström, 1932: 192,  syn. nov.     Copelatus collocallosus Falkenström, 1933: 14; synonymy by  Gschwendtner (1939: 40).     Typelocality.  Copelatus chinensis: Chine: Chang-Yang[ China, Hubei Province, Changyang Tujia Autonomous County].   Copelatus collocallosus: “ China: NO Szechuan” [ China, northeast Sichuan Provinceor ChongqingMunicipality].  Type material.  Copelatus chinensis:  Holotype ♂( MNHN), labelled: “Chang- / Yang[hw] // MUSEUM PARIS / COLL MAURICEREGIMBART / 1908 [p] // TYPE [red label, p] // chinensis Rég.[hw] // GUIGNOT det., 19 [p] 51 [hw] / Copelatus/ japonicus Sharp[hw]”.   Copelatus collocallosus:  Holotype ♀( NHRS), labelled: “Kina / N. O. Szechuan[p] // Sven Hedins / Exp. Ctr. Asien / Dr Hummel[p] // 22.5 [hw] // Typus [red label with black frame, p] // Cop. collocallosus/ n. sp. / Typ. [hw] / det. Falkenström[p] // 5606 / E91 [blue label, p] // NHRS/JLKB / 000027137 [p]”.  Additional material examined.   CHINA: Hunan: 1 ♂, 1 ♀,  80 kmN Dayong, Yanjiajie,  27.-29.v.2005, O. Nakládalleg. ( NMPC);  2 ♂, 1 ♀, Shaoyang, Chengbu County, Jinzishan forestfarm, Shuangjiangkou, 26.3046N 110.4961E,  1371 m,  24.viii.2020, Z. Jiangleg. ( SYSU).   Shandong: 1 ♀, Qingdao City,  17.ix.1994, Ji& Wangleg.;  1 ♀, Taishan Nat. Res.,  200 m,  18.x.1994, Ji& Wangleg.;  1 ♂, Taishan Nat. Res.,  420 m,  19.x.1994, Ji& Wangleg. (all NHMW).   Zhejiang: 45 spec., West Tianmu Shan (Mts.) reserve, border of secondary mixed forest nr entrance of reserve, 30°18.9′N 119°26.5′E,  320 m, pool,  23.vi.-6.vii.2017, J. Hájek& J. Růžičkaleg. ( NMPC, SNUC, ZSMG);  1 ♂, 1 ♀, Quzhou, Kecheng distr., Lankeshan Mt., 28.8781N 118.9199E,  118 m,  18.iii.2020, Z. Jiangleg. ( SYSU);  1 ♂, Quzhou, Qujiang distr., Tongshanyuanreservoir, 29.1300N 118.9434E,  93 m,  14.iii.2020, Z. Jiangleg. ( SYSU).   Diagnosis.Medium sized (TL: 4.6–5.3 mm), oblong-oval species. Head with reddish clypeus, frons and vertex darkened, brown blackish; pronotum brown blackish, laterally broadly testaceous; elytra brown with broad, irregularly shaped, basal orange band reaching suture. Pronotum with short longitudinal strioles laterally. Each elytron with six complete discal striae and one submarginal stria: all striae beginning at base; stria 1 longest, ending close to apex; striae 2–5 somewhat shorter, ending subapically, even striae generally shorter than odd striae; stria 6 ending at apical fourth; submarginal stria long, beginning before elytral mid-length and ending at apical fourth ( Fig. 2). Median lobe of aedeagus in lateral view sickle-shaped, narrowing in apical fourth to skewed, dorsally slightly extended apex; dorsal and ventral side of apical part straight ( Fig. 31). Parameres moderately broad, ‘C’-shaped; apex short and broad; apical lobes long, club-shaped ( Fig. 32). Female similar to male, strioles on pronotum more numerous.   Comments on the classification. Guignot (1952)synonymized  C. chinensiswith  C. japonicus Sharp, 1884based on the drawing of median lobe of the latter species by Balfour-Browne (1947). However, the dissection of the holotypeof  C. chinensisrevealed that the genitalia of both taxa are quite different (see Figs 31and 39). Therefore, we reinstate  C. chinensisas a valid species.   Copelatus collocallosuswas described twice, based on a single teneral female ( Fig. 3); the first brief description ( Falkenström 1932) was subsequently supplemented with a differential diagnosis from  C. chinensis: pale colouration, different body shape, indistinct punctation, small number of extremely short strioles on the pronotum, rather long submarginal stria ( Falkenström 1933). Gschwendtner (1939)was the first who considered  C. collocallosusas a synonym of  C. chinensis; however, probably based on synonymy of  C. chinensiswith  C. japonicusby Guignot (1952), Satô (1982) mentioned  C. collocallosusas a synonym of  C. japonicus– a state which was largely accepted until now (cf. Nilsson 1995, Nilsson & Hájek 2022a). However, our study confirmed specific status of  C. chinensis(see above). Further, in accordance with Gschwendtner (1939), the comparison of the  C. collocallosus holotypewith the extensive material of  C. chinensisshowed that both taxa are morphologically indistinguishable, including identical punctation of dorsal surface, presence of strioles on pronotum and length of elytral striae. Therefore, we consider  C. collocallosusas a junior subjective synonym of  C. chinensis, although we are aware that the identity of  C. collocallosusis doubtful as the teneral female does not possess characters usable for species identification – the species of the  C. japonicuscomplex are recognisable predominantly based on male genitalia. Anyway, the synonym of  C. chinensisand  C. collocallosusalso seems reasonable from a biogeographical point of view:  C. chinensisis widely distributed in Central China, and its type locality in Hubeilies only ca. 100 apart from the border of ChongqingMunicipality (a presumed type locality of  C. collocallosus).  Collection details.In Tianmushan ( Zhejiang),  Copelatus chinensiswas collected in number in exposed side pool of a river with sandy bottom ( Fig. 71); few specimens were found also in shaded forest puddle with muddy bottom.   Distribution.Central and eastern China( Hubei, Hunan, Shandong, Sichuanor Chongqing, and Zhejiangprovinces) ( Fig. 81). 3746435418 China Changyang Tujia Autonomous County Chang-Yang 2 253 1 Hubei holotype 3746435438 MNHN Mauritius Yang 3 254 1 1 holotype 3746435364 NHRS N. O. Szechuan Falkenstrom 3 254 1 1 holotype 3746435476 2005-05-27 2005-05-29 2005-05-27 NMPC O. Nakladal China Yanjiajie 3 254 2 1 1 Hunan 3746435440 2020-08-24 SYSU Z. Jiang China Chengbu County 1371 26.3046 Jinzishan forest 6 110.4961 Shaoyang 3 254 3 1 2 Hunan 3746435450 [781,1431,438,465] 1994-09-17 Ji & Wang China Qingdao City 3 254 1 1 Shandong 3746435341 [151,813,475,501] 1994-10-18 Ji & Wang China 200 Taishan Nat. Res. 3 254 1 1 Shandong 3746435422 1994-10-19 NHMW Ji & Wang China 420 Taishan Nat. Res. 3 254 1 1 Shandong 3746435460 2017-06-23 2017-07-06 2017-06-23 NMPC, SNUC, ZSMG J. Hajek & J. Ruzicka China 320 30.315 West Tianmu Shan (Mts.) reserve 121 119.441666 3 254 45 Zhejiang 3746435342 2020-03-18 SYSU Z. Jiang China Quzhou 118 28.8781 Lankeshan Mt. 6 118.9199 Kecheng distr. 3 254 2 1 1 Zhejiang 3746435393 2020-03-14 SYSU Z. Jiang China Quzhou 93 29.13 Tongshanyuan 6 118.9434 Qujiang distr. 3 254 1 1 Zhejiang