Five new species of Pelthydrus Orchymont, 1919 from China and adjacent countries (Coleoptera: Hydrophilidae) Author Bian, Dongju Author Schönmann, Heinrich Author Ji, Lanzhu text Zootaxa 2009 2118 53 64 journal article 10.5281/zenodo.188028 2b8fa774-e232-44d4-b85e-4c4b3205265d 1175-5326 188028 Pelthydrus subgrossus sp. nov. ( Fig. 3 ) Type material. Holotype (IAECAS) male: “ CHINA : Hubei Province. 24. 10. 2004 / Zhongjian He Nat. Res./ 105 km S Enshi, Xianfeng/ 650 m , leg. Schönmann/ & Wang ( CWBS 551)”. Paratypes : 4 exs. ( NMW ), the same data as holotype . Diagnosis. This species is similar to Pelthydrus grossus sp. nov. , but can be distinguished from it by its smaller size, and thicker median lobe of aedeagus. Description. Body length 3.1 mm – 3.3 mm ; width 2.0 mm– 2.2 mm . broadly oval and distinctly convex, somewhat acute in posterior portion; complete surface shining, dark black; lateral margins of head, pronotum, labial and maxillary palpi, tibae and tarsi reddish brown, antennae yellowish brown. Head trapezoidal, about 1.8 times wider than long; gradually widened towards posterior part; lateral sides smooth; median-sized punctures densely distributed; innersides of eyes distinctly wrinkled; clypeal suture distinct; anterior margin of clypeus truncated, anterior corners roundly angulate. Pronotum trapezoidal, about 2.3 times wider than long, punctuation a little larger than that on head; lateral margins narrowly ridged, anterior margin somewhat arched at middle; anterior corners angulated, posterior corners broadly rounded. Elytra about 1.3 times longer than wide; broadest part at one fourth from base, from there distinctly narrowed posteriorly; punctuation much smaller and sparser than head and pronotum. Ventral side mostly reddish brown to dark brown; mentum dark brown, somewhat rugulose; prosternum yellowish with a medio-longitudinal carina; mesosternum elevated posteriorly producing a triangular plate, which has a round apical part and a longitudinal carina at middle; metasternum has a “M” shaped projection at base, and elevated towards posterior part, with an elongate oval and glabrous area posteriorly. Aedeagus ( Fig. 3 ). 0.67 mm long, nearly paralleled, phallobase approximately as long as the median lobe; median lobe very thick, with paralleled sides, ending with a round point; parameres a little longer than median lobe with sharp apices at innersides. Distribution. China (Hubei Province). Etymology. This species is named in reference to its similarity with Pelthydrus grossus sp. nov.