Batraxis

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 : 10

Key to Batraxis males from Hainan

1 Body less than 1.4 mm ( Fig. 3 B)............................................................. B. minor sp. n.

- Body more than 1.5 mm ............................................................................... 2

2 Dorsal surface of body with bushy, long pubescence ( Fig. 2 A)....................................... B. pilosa sp. n.

- Dorsal surface of body shiny, glabrous or sometime with sparse, minute setae..................................... 3

3 Abdomen and elytra bicolorous ( Fig. 1 A)...................................................... B. bicolor sp. n.

- Abdomen and elytra concolorous........................................................................ 4

4 Abdomen strongly narrowed at lateral margins near base ( Fig. 1 B); profemora protuberant at middle ( Fig. 5 F)..................................................................................................... B. tibialis sp. n.

- Abdomen smoothly rounded basolaterally or straight; profemora lacking protuberance............................... 5

5 Mesotibiae with a sharp apical tooth ( Fig. 5 E)................................................. B. spinosas sp. n.

- Mesotibiae simple.................................................................................... 6

6 Head with complete vertexal sulcus, anterior margin of vertexal sulcus merging with subantennal transverse sulcus; antennae relatively thick ( Fig. 4 A); protrochanters lacking protuberance at ventral margin ( Fig. 4 E)............... B. simplex sp. n.

- Head lacking vertexal sulcus; antennae relatively thin ( Fig. 3 A); protrochanters expanded ventrally ( Fig. 5 K).................................................................................................. B. hainanensis sp. n.

Figures

FIGURE 1. Dorsal habitus of Batraxis species. A. B. bicolor. B. B. tibialis. Scale line: 0.3 mm.

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

FIGURE 3. Dorsal habitus of Batraxis species. A. B. hainanensis. B. B. minor. Scale line: 0.3 mm.

FIGURE 4. Diagnostic features of male Batraxis simplex. A. Dorsal habitus. B. Aedeagus, in dorsal view. C. Same, in later view. D. Same, in ventral view. E. Protrochanter. Scale line: A = 0.3 mm; B, C, D, E = 0.05 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.