A review of Copelatus Erichson, 1832 of Mainland China, with description of ten new species from the japonicus complex (Coleoptera: Dytiscidae: Copelatinae) Author Jiang, Zhuo-Yin 0000-0001-6825-4283 State Key Laboratory of Biocontrol and Institute of Entomology, Sun Yat-sen University, Guangzhou 510275, China. zhuoyin _ jiang @ 126. com; https: // orcid. org / 0000 - 0001 - 6825 - 4283 Author Zhao, Shuang Guangzhou Customs Technology Center, Nansha District, Guangzhou, China. Author Yang, Zhen-Yu Brilliant Landscaping and Gardening Company Limited, Macau. Author Jia, Feng-Long 0000-0003-2391-5038 State Key Laboratory of Biocontrol and Institute of Entomology, Sun Yat-sen University, Guangzhou 510275, China. fenglongjia @ aliyun. com; lssjfl @ mail. sysu. edu. cn; http: // orcid. org / 0000 - 0003 - 2391 - 5038 fenglongjia@aliyun.com Author Hájek, Jiří 0000-0001-5779-1542 Department of Entomology, National Museum, Cirkusová 1740, CZ- 193 00 Praha 9 - Horní Počernice, Czech Republic. jiri. hajek @ nm. cz; https: // orcid. org / 0000 - 0001 - 5779 - 1542 jiri.hajek@nm.cz text Zootaxa 2022 2022-04-04 5124 3 251 295 journal article 53387 10.11646/zootaxa.5124.3.1 de55f596-c349-4ca2-a826-0e2bad912aa3 1175-5326 6410696 67D4C618-C7C2-4FFC-925B-B260E11CD7B4 Copelatus chinensis Régimbart, 1899 stat. rest. ( 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) . Type locality. Copelatus chinensis : Chine: Chang-Yang [ China , Hubei Province , Changyang Tujia Autonomous County ] . Copelatus collocallosus : “ China : NO Szechuan” [ China , northeast Sichuan Province or Chongqing Municipality]. Type material. Copelatus chinensis : Holotype ♂ ( MNHN ), labelled: “Chang- / Yang [hw] // MUSEUM PARIS / COLL MAURICE REGIMBART / 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 km N Dayong , Yanjiajie , 27.-29.v.2005 , O. Nakládal leg. ( NMPC ) ; 2 ♂ , 1 ♀ , Shaoyang , Chengbu County , Jinzishan forest farm, Shuangjiangkou , 26.3046N 110.4961E , 1371 m , 24.viii.2020 , Z. Jiang leg. ( SYSU ) . Shandong : 1 ♀ , Qingdao City , 17.ix.1994 , Ji & Wang leg. ; 1 ♀ , Taishan Nat. Res. , 200 m , 18.x.1994 , Ji & Wang leg. ; 1 ♂ , Taishan Nat. Res. , 420 m , 19.x.1994 , Ji & Wang leg. (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. Růžička leg. ( NMPC , SNUC , ZSMG ) ; 1 ♂ , 1 ♀ , Quzhou , Kecheng distr. , Lankeshan Mt. , 28.8781N 118.9199E , 118 m , 18.iii.2020 , Z. Jiang leg. ( SYSU ) ; 1 ♂ , Quzhou , Qujiang distr. , Tongshanyuan reservoir, 29.1300N 118.9434E , 93 m , 14.iii.2020 , Z. Jiang leg. ( 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. chinensis with C. japonicus Sharp, 1884 based on the drawing of median lobe of the latter species by Balfour-Browne (1947) . However, the dissection of the holotype of C. chinensis revealed that the genitalia of both taxa are quite different (see Figs 31 and 39 ). Therefore, we reinstate C. chinensis as a valid species. Copelatus collocallosus was 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. collocallosus as a synonym of C. chinensis ; however, probably based on synonymy of C. chinensis with C. japonicus by Guignot (1952) , Satô (1982) mentioned C. collocallosus as 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 holotype with the extensive material of C. chinensis showed 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. collocallosus as a junior subjective synonym of C. chinensis , although we are aware that the identity of C. collocallosus is doubtful as the teneral female does not possess characters usable for species identification – the species of the C. japonicus complex are recognisable predominantly based on male genitalia. Anyway, the synonym of C. chinensis and C. collocallosus also seems reasonable from a biogeographical point of view: C. chinensis is widely distributed in Central China , and its type locality in Hubei lies only ca. 100 apart from the border of Chongqing Municipality (a presumed type locality of C. collocallosus ). Collection details. In Tianmushan ( Zhejiang ), Copelatus chinensis was 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 , Sichuan or Chongqing , and Zhejiang provinces) ( Fig. 81 ).