Batrisodes grossepunctatus Zhang & Yin, 2021

Zhang, Wen-Xuan & Yin, Zi-Wei, 2021, Two new species of Batrisodes Reitter from Shaanxi, China (Coleoptera Staphylinidae: Pselaphinae), Zootaxa 4938 (2), pp. 243-250 : 247-248

Batrisodes grossepunctatus Zhang & Yin , sp. nov.

( Figs 3 , 4 )

Type material. HOLOTYPE: CHINA: ♂, ‘ China: Shaanxi, Nanzheng County (Ɯfflfl), Liping Forest Park (= ḢÑẎƙfin'ẘ), 32°50′20″N, 106°36′18″E, 15.vii.2012, 1400–1600m, mixed leaf litter, sifted, Y.-H. Pan leg.’ ( SNUC) . PARATYPES: CHINA: 1 ♂, 3 ♀♀, same label data as for holotype ( SNUC); 1 ♂, same label data as for holotype, except ‘ 16.vii.2012, Li Li-Zheng leg.’ ( SNUC) .

Diagnosis. Male. Body length 2.41–2.48 mm. Head base rounded, wider than pronotum; frons with anterolateral margin greatly protruding anteriorly, deeply and roundly concave at middle; clypeus with large projection at middle, sides of projection narrowing posteriorly from apical 1/ 3 in dorsal view. Pronotum roughly punctate, with four distinct discal teeth. Mesofemur with long ventral spine near middle, mesotibia expanded for apical 1/3 of tibial length, with blunt projection before middle. Aedeagus dorso-ventrally symmetric, with symmetric, well-sclerotized endophallus. Female. Similar to male in external morphology, lacking modifications on head and legs; may be identified only by geographical association with male.

Description. Male ( Fig. 3A ). Body reddish brown, length from anterior margin of clypeus to apex of abdomen 2.41–2.48 mm. Head ( Fig. 4A ) slight wider than long, length from anterior margin of clypeus to head base (excluding occipital constriction) 0.52–0.54 mm, width across eyes 0.57–0.59 mm; surface roughly punctate, with large, nude vertexal foveae; frons with anterolateral margin greatly protruding anteriorly, deeply and roundly concave at middle; clypeus with large projection at middle, margins of projection narrowing posteriorly from apical 1/ 3 in dorsal view. Clypeal anterior margin rounded; lateral vertexal carina faint, extending from occipital constriction to level of posterior margin of eyes, mediobasal carina weakly extending from head base to level of anterior margin of eyes. Eyes relatively small, each composed of approximately 40 facets. Antenna lacking distinct club, antennomere 1 (scape) thick, subcylindrical, antennomeres 2–10 moniliform, antennomeres 2–8 of similar width, antennomere 9 wider than 8, antennomeres 9 and 10 successively broader, each strongly transverse, antennomere 11 largest, subconical, lacking hook-like spine. Pronotum approximately as long as wide, length along midline 0.50 mm, maximum width 0.49 mm; sides rounded, widest near the middle, disc slightly convex, roughly punctate, with four distinct teeth; median longitudinal sulci weekly present; lateral longitudinal sulci distinct; with small nude median and setose lateral antebasal foveae; outer and inner pair of basolateral foveae distinct. Elytra wider than long, length along suture 0.64–0.65 mm, maximum width 0.78–0.81 mm; each elytron with three large, nude basal foveae, inner two close; discal striae shallow and short, extending posteriorly for 1/3 of elytral length. Mesofemur ( Fig. 4C ) with thin but distinct ventral spine near middle, mesotibia expanded for apical 1/3 of tibial length, with blunt ventral projection at apical 2/5, apex of projection rounded, with dense short setae. Abdomen widest at lateral margins of tergite 1 (IV), length of dorsally exposed part along midline 0.74–0.79 mm, maximum width 0.75–0.79 mm; tergite 1 (IV) with strongly oblique marginal carinae, discal carinae thick, tergite 5 (VIII) ( Fig. 4D ) semicircular; sternite 6 (VIII) ( Fig. 4E ) transverse. Aedeagus ( Fig. 4F, G ) 0.45 mm long, median lobe dorso-ventrally symmetrical and flattened, broadest near apex, apical part narrowing toward apex and curved ventrally in lateral view; endophallus well-sclerotized, lateral lobes broad at bases, abruptly constricted at middle and then evenly narrowing apically.

Female ( Fig. 3B ). General morphology similar to male, lacking modifications on head ( Fig. 4B ) and legs; each eye composed of about 20 facets; genital complex ( Fig. 4H ) symmetrical, weakly sclerotized, 0.27 mm wide. Measurements of body parts (as for male): body length 2.52–2.53 mm, length/width of head 0.51–0.52 mm / 0.57 mm, pronotum 0.52–0.53 mm / 0.49–0.50 mm, elytra 0.66–0.67 mm / 0.80–0.81 mm, abdomen 0.80–0.84 mm / 0.80 mm.

Comparative notes. The new species is morphologically most similar to B. grandiceps sp. nov. described above by the male having a similar position and shape of the cephalic modifications and spination of the legs, as well as the presence of a well-sclerotized endophallus of the aedeagus. They can be clearly separated by the larger body size (2.41–2.48 mm vs. 2.29–2.35 mm), the posteriorly narrowing sides of the projection on the clypeus, the roughly punctate pronotal disc, and the different shape of the lateral lobes of the aedeagal endophallus of the new species.

The modified male head is not an uncommon character state in Asian Batrisodes . However, a roundly and deeply excavated anterior margin of the frons occurs only in B. babaianus Nomura distributed in Meifeng (Ṙữ), Taiwan. The two new species described here can be readily separated from B. babaianus by the presence of a large projection on the clypeus, which is lacking in the latter species.

Distribution. China: Shaanxi.

Etymology. The new specific epithet refers to the roughly punctate pronotum of the new species.

Figures

FIGURE 3. Dorsal habitus of Batrisodes grossepunctatus sp. nov. A. Male. B. Female. Scale bars: 0.5 mm.

FIGURE 4. Diagnostic characters of Batrisodes grossepunctatus sp. nov. (A, C, D–G. Male. B, H. Female) A, B. Head and pronotum. C. Mesofemur and mesotibia. D. Tergite VIII. E. Sternite VIII. F, G. Aedeagus, in lateral (F) and ventral (G) view. H. Female genitalia. Scale bars: 0.3 mm in A–C; 0.2 mm in F, G; 0.1 mm in D, E, H.