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 : 14-15

Key to Batraxis females from Hainan

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

- Body relative big, more than 1.5 mm ...................................................................... 2

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

- Dorsal surface of body shiny, glabrous or sometimes with sparse, short setae..................................... 3

3 Abdomen strongly narrowed at lateral margin near base ( Fig. 1 B)................................... B. tibialis sp. n.

- Abdomen smoothly rounded laterally or straight............................................................ 4

4 Protibiae expanded at middle; mesotibiae expanded at basal fourth and apical third,.. metatibiae expanded at basal fourth and apex ( Fig. 1 A)............................................................................ B. bicolor sp. n.

- All tibiae thin........................................................................................ 5

5 Head with complete subantennal transverse sulcus, anterior margin of vertexal sulcus margin merging with subantennal transverse sulcus; antennae relatively thick; discal carinae of tergite IV widely separate ( Fig. 4 A)............. B. simplex sp. n.

- Head with abrupt subantennal transverse sulcus, lacking vertexal sulcus; antennae relatively. thin, discal carinae of tergite IV relatively close....................................................................................... 6

6 Discal carinae of tergite IV slightly divergent, width between discal carinae 1/3 width of tergite IV ( Fig. 3 A).................................................................................................. B. hainanensis sp. n.

- Discal carinae of tergite IV divergent, close at bases, width between discal carinae 1/9 width. of tergite IV at bases ( Fig. 2 B)....................................................................................... B. spinosas 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.