Batraxis yifan, Wang, Dan & Yin, Zi-Wei, 2016

Wang, Dan & Yin, Zi-Wei, 2016, New species and records of Batraxis Reitter (Coleoptera: Staphylinidae: Pselaphinae) in continental China, Zootaxa 4147 (4), pp. 443-465 : 452-454

Batraxis yifan , new species

( Figs 5 B, 12D–F, 14G, 14S, 15)

Type material (6 ƋƋ, 7 ♀♀). Holotype: CHINA: Ƌ, labeled ‘ CHINA: Yunnan Province, Lincang City (临沧市), Yun Hsien (云县), Manwan Town (漫湾镇), Shuibatou Village (水坝头村), 24°40'29''N, 100°18'50''E, 2417m, 14.iii.2016, Zi-Chun Xiong leg.’ ( SNUC) . Paratypes: CHINA: 4 ♂♂, 6 ♀♀, same label data as holotype ( SNUC) ; 1 Ƌ, 1 ♀, same data as previous material except ‘ 10.ii.2016 ’ ( SNUC) .

Diagnosis of male. Body almost glabrous, elytra and abdomen with sparse, minute pubescence; frons with complete subantennal transverse sulcus; antennomeres IX slightly elongate, XI obliquely narrowed at apex; pronotum with distinct median antebasal fovea, lacking basal impression; all tibiae slender; protrochanters protuberant ventrally, profemora simple, protibiae lacking protuberance, mesotibiae with apical spur; tergite IV with narrow basal sulcus, discal carinae relatively long, close, with relatively long marginal carinae; aedeagus relatively elongate.

Description. Male ( Fig. 5 B). Body almost glabrous, dark-brown, length 2.19–2.20 mm. Head rectangular, slightly longer than wide, HL 0.47–0.49 mm, HW 0.47 mm, vertex moderately convex, with pair of distinct vertexal foveae; antennal tubercles low; frons flattened, subantennal transverse sulcus abrupt, with indistinct vertexal sulcus merging with subantennal transverse sulcus and connecting foveae; each eye composed of about 30 facets; antennae thin, antennomeres III‒IX elongate, X slightly transverse, XI largest, widest at middle; median gular carina relatively narrow, with two separated nude foveae. Pronotum slightly wider than long, PL 0.40–0.42 mm, PW 0.48–0.50 mm, with distinct median antebasal fovea, lacking basal impression. Elytra wider than long, EL 0.67–0.69 mm, EW 0.83–0.84 mm, each elytron with two shallow foveae at base. Protrochanters weakly protuberant at ventral margin ( Fig. 14 S), mesotibiae with apical tooth ( Fig. 14 G). Abdomen slightly wider than long, AL 0.62–0.63 mm, AW 0.72–0.74 mm, slightly expanded at base; tergite IV (first visible tergite) with narrow basal sulcus; discal carinae relatively long, close, extending to apical one-third of tergal length, width between carinae 0.17–0.18 mm at apices; marginal carinae extending to half of tergal length. Aedeagus ( Fig. 12 D–F) 0.34 mm in length, relatively elongate, parameres distinctly exceeding apex of median lobe, protuberant at apicolateral margins, each with three apical setae; endophallus with two long sclerites and numerous spine-like structures, inclining toward right.

Female. Similar to male in general appearance; protrochanters and mesotibiae simple; each eye composed of about 30 facets. Measurements: BL 2.11–2.13 mm; HL 0.48–0.50 mm; HW 0.47–0.48 mm; PL 0.39–0.40 mm; PW 0.45–0.47 mm; EL 0.66–0.67 mm; EW 0.81–0.83 mm; AL 0.54–0.60 mm; AW 0.73–0.74 mm; width between discal carinae of tergite IV 0.16–0.18 mm at apices.

Comparative notes. Batraxis yifan is close to B. spinosas Wang & Yin by the similar general habitus, presence of an apical tooth on the mesotibiae, and aedeagus with parameres distinctly exceeding the apex of the median lobe. These two species can be readily separated by the presence of a distinct pronotal median fovea, and tergite IV with parallel discal carinae in the new species, and the aedeagal parameres are protuberant at apicolateral margins. In comparison, B. spinosas has an indistinct, shallow median fovea on the pronotum, the discal carinae of tergite IV are distinctly divergent, and the aedeagal parameres lack protuberance at lateral margins.

Distribution. China: Yunnan ( Fig. 15 ).

Etymology. The specific epithet ‘ yifan’ is the nick name of the collector’s nephew.

Figures

FIGURE 5. Dorsal habitus of Batraxis species. A. B. nanlingensis (female). B. B. yifan (male). Scale bars: 0.5 mm.

FIGURE 12. Aedeagi of Batraxis species. (A, B, D, E, G, H. in ventral view. C, F, I. in lateral view). A – C. B. nanlingensis. D – F. B. yifan. G – I. B. ziyueae. Scale bars: 0.1 mm.

FIGURE 14. Legs of male Batraxis species. (A – F. Protibia. G. Mesotibia. H, I. Profemur. J – V. Protrochanter). A, K. B. gloriosa, population from Fujian. B, L. B. gloriosa, population from Zhejiang. C, H, P. B. gesar. D, T. B. ziyueae. E, U. B. bicolor, population from Yunnan. F, I, V. B. tibialis, population from Jiangxi. G, S. B. yifan. J. B. gloriosa, population from Hunan. M. B. gloriosa, population from Jiangxi. N. B. gloriosa, population from Guangxi. O. B. longicornis. Q. B. longithorax. R. B. nanlingensis. Scale bars: A ‒ I = 0.1 mm; J ‒ V = 0.05 mm.

FIGURE 15. Distribution of Batraxis species in China.