Figures 17 - 22 in A new species of Laccobius Erichson, 1837 (Hydrophilidae, Coleoptera) from the Chinese Himalaya, with comments on taxonomic status of subgenera Glyptolaccobius Gentili, 1989 and Cyclolaccobius Gentili, 1991 and additional faunistic records from China

Figures 17-22. Male genitalia of the species similar to Laccobius motuoensis sp. nov. 17-19 L. sipeki Gentili & Fikáček, holotype (17 ventral 18 lateral 19 ventral) 20-22 L. yunnanensis Gentili, specimen from China: Yunnan: Rehai Hot springs (coll. NMPC) 20 detail of the apical half of medial lobe 21 ventral view 22 lateral view.
1Elytra with distinct parasutural furrows2-Elytra without distinct parasutural furrows32Body length 2.7-2.9 mm; elytra without pale yellow spots at base; median lobe bearing lateral subapical rows of stout spines (Jia et al, 2013: figs 3-5)L. qinlingensis Jia, Gentili & Fikáček-Body length 1.8-2.1 mm; base of elytra with two or four distinct pale yellow spots; median lobe without lateral subapical rows of spines (Zhang and Jia 2017: figs 6, 7)L. yinziweii Zhang & Jia3Body length 2.0-2.8 mm; elytral borders and epipleura are swollen at base; median lobe narrowly pointed apically (Gentili 1995: figs 52, 53)L. nitidus Gentili-Body length 1.8-2.1 mm; elytral borders and epipleura are not swollen at base; median lobe rounded apically44Apical part of the median lobe without series of fine setae. Elytra completely black at the base. Species from Hainan and Taiwan5-Apical part of the median lobe with series of fine setae. Elytra with or without pale basal spots. Continental species65Median lobe strongly constricted subapically (Jia et al. 2013: figs10-12). HainanL. hainanensis Jia, Gentili & Fikáček-Median lobe indistinctly constricted subapically (Jia et al. 2013: figs 14-16). TaiwanL. politus Gentili6Elytral series regular throughout; primary series of punctures distinctly stronger and coarser than secondary ones; median lobe ca. of the same width in apical half (Figs 5, 6)L. motuoensis sp. nov.-Elytral series somewhat irregular at base, with some secondary punctures at least as large as those on primary series; median lobe distinctly widened apically (Figs 20-22)L. yunnanensis Gentili