Batraxis pilosa Wang and Yin

Wang, Dan, Yin, Zi-Wei & Wang, Chun-Xin, 2016, On a collection of Batraxis Reitter (Coleoptera: Staphylinidae: Pselaphinae) from Hainan Island, southern China, Zootaxa 4109 (1), pp. 1-15 : 4-6

3. Batraxis pilosa Wang and Yin , new species

( Figs 2 A, 5C, 5I, 7A–C)

Type material (3 ♂♂, 1 ♀). Holotype: CHINA: ♂, labeled ‘ CHINA: Hainan, Qiongzhong Hsien, Limu Mt., path to Limu Temple, 19°08–09'N, 109°45–46'E, 580–760 m, 29.i.2015, Peng, Yin, Tu, Song, Shen, Zhou, Yan leg,’. Paratypes: CHINA: 2 ♂♂, 1 ♀, same label data as holotype.

Diagnosis of male. Body pubescent; frons with complete subantennal transverse sulcus; vertex with a median pit; antennomeres IX transverse; pronotum with distinct median antebasal fovea and basal impression; all tibiae thin; protibiae protuberant near apex, mesotibiae lacking apical spur; protrochanters protuberant ventrally; tergite IV with broad, abrupt basal sulcus; discal carinae long, widely separated; with relatively long marginal carinae; aedeagus relatively elongate.

Description. Male ( Fig. 2 A). Body reddish-brown, pubescent, length 2.05 mm. Head rectangular, slightly longer than wide, HL 0.48 mm, HW 0.42 mm, vertex moderately convex, with median pit in middle of small but distinct vertexal foveae; antennal tubercles raised; frons with complete subantennal transverse sulcus, lacking vertexal sulcus; each eye composed of about 20 facets; antennae thick, antennomere III–VII as long as wide, VIII slightly transverse, IX distinctly transverse, X transverse, XI largest, widest near base, then obliquely narrowing toward apex; median gular carina narrow, with two clearly separated small nude gular foveae. Pronotum slightly wider than long, PL 0.40 mm; PW 0.45 mm, with distinct median antebasal fovea and complete basal impression, with pair of lateral antebasal foveae and outer pair of basolateral foveae. Elytra wider than long, EL 0.53 mm, EW 0.74 mm, with two pairs of distinct foveae at base. Protrochanters strongly protuberant at ventral margin ( Fig. 5 I); protibiae with small tooth preapically ( Fig. 5 C). Abdomen wider than long, AL 0.64 mm, AW 0.72 mm, distinctly narrowed at base; tergite IV (first visible tergite) with broad, abrupt basal sulcus; discal carinae elongate, widely separated, extending to two-thirds of tergal length, width between discal carinae 0.38 mm at apices; marginal carinae extending to apical two-thirds of tergal length. Aedeagus ( Fig. 7 A–C) 0.39 mm in length, relatively elongate, parameres slightly exceeding apex of median lobe, rounded apically, each with one preapical seta; endophallus with series of symmetric sclerites and small, weakly sclerotized median sclerite.

Female. Very similar to male in general appearance; protrochanters and tibiae lacking spur; each eye composed of about 10 facets. Measurements: BL 2.02 mm; HL 0.48 mm; HW 0.43 mm; PL 0.40 mm; PW 0.45 mm; EL 0.52 mm; EW 0.76 mm; AL 0.62 mm; AW 0.73 mm; width between discal carinae of tergite IV 0.38 mm at apices.

Comparative notes. The unique combination of characters of Batraxis pilosa quickly separates this species from all other congeners from Hainan, i.e. the long pubescence of the body, the presence of a median pit between the vertexal foveae in both sexes, the strongly raised antennal tubercles, and the aedeagus with apically rounded parameres slightly exceeding the median lobe, and with complicated and symmetric endophallus.

Distribution. Southern China: Hainan.

Etymology. The specific epithet refers to the dense pubescence of the body.

Figures

FIGURE 2. Dorsal habitus of Batraxis species. A. B. pilosa. B. B. spinosas. Scale lines: 0.3 mm.

FIGURE 5. Diagnostic features of male Batraxis species. (A – D. Protibia. E. Mesotibia. F. Mesofemur. G – L. Protrochanter). A, G. B. bicolor. B, F, H. B. tibialis. C, I. B. pilosa. D, E, J. B. spinosas. K. B. hainanensis. L. B. minor. Scale line: 0.1 mm.

FIGURE 7. Aedeagi of Batraxis species. (A, D. in dorsal view. B, E. in lateral view. C, F. in ventral view). A – C. B. pilosa. D – F. B. spinosas. Scale line: 0.1 mm.