A taxonomic revision of the genus Sinotrisus Yin & Li (Coleoptera, Staphylinidae, Pselaphinae) Author Yin, Zi-Wei Author Nomura, Shuhei Author Li, Li-Zhen text ZooKeys 2012 205 45 57 http://dx.doi.org/10.3897/zookeys.205.3362 journal article http://dx.doi.org/10.3897/zookeys.205.3362 1313-2970-205-45 Sinotrisus vietnamensis Yin & Nomura sp. n. Figs 4B, 6 Type material. Holotype, male, labeled 'Mt. Phang Si Pang (moss: / 2,000 m). Lai Chau Prov. / [N. VIETNAM] / 17.v.2003, S. Nomura leg. // HOLOTYPE [red] / Sinotrisus vietnamensis sp. n. / Yin and Nomura / det. 2012, NSMT' . Diagnosis. Vertex modified in male. Antennomeres VII greatly transverse. Pronotum lacking spines along discal ridges; basolateral foveae small. Mesotibiae with apical spur about as long as first tarsomeres. Description. Male (Fig. 4B). Length 3.00. Head (Fig. 6A) distinctly wider than long, HL 0.57, HW 0.71; frons convex medially, extending posteriorly to anterior mar gin of vertexal cavity; shallow transverse cavity with large foveae, area posterior to cavity strongly raised medially to form rostrum, densely covered with setae; with distinct occipital carinae; postocular margins evenly narrowed toward head base; antennomeres IV (Fig. 6B) about same length as VI, clubs formed by apical three antennomeres, IX strongly transverse, X slightly longer than IX, XI nearly oval, narrowed toward apex in apical half. Pronotum about as long as wide, PL 0.63, PW 0.65; median longitudinal sulcus slightly widened posteriorly to form shallow oval antebasal impression, lacking median antebasal fovea; paranotal carinae extending through length of prosternum. Elytra slightly wider than long, EL 0.92, EW 1.13; barely angulate at humeri. Mesotrochanters (Fig. 6C) with long basoventral spine; mesotibiae with apical spur (Fig. 5D) about same length of first tarsomeres; metatrochanters (Fig. 6E) broadly expanded ventrally, with small blunt tubercle at ventral margin. Abdomen slightly wider than long, AL 0.88, AW 1.10; segments lacking basal ridges. Aedeagus (Figs 6 F-I ) well-sclerotized, length 0.39. Female. Unknown. Figure 6. Sinotrisus vietnamensis A head and pronotum B antenna C mesotrochanter D apex of mesotibia E metatrochanter F aedeagus, in top view G same, in dorsal view H same, in lateral view I same, in ventral view. Scales (mm): A, B = 0.5; C, D, E = 0.1; F, G, H, I = 0.2. Distribution. Vietnam: Lai Chau. Habitat. The individual was collected from a pile of moist moss. Etymology. Named after the country where the type locality lies.