Neosclerus incisus, Assing, 2011

Assing, Volker, 2011, A revision of the genus Neosclerus C (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 6 (1), pp. 89-148 : 112-114

Neosclerus incisus sp. n. ( Figs 60-65)

Type material:

Holotype  [slightly teneral]: " China, Guangxi, Nongxin , 1020 m, 12.VIII.1998, J.R. Fellowes / Holotypus  Neosclerus incisus sp. n. det. V. Assing 2010 " (cAss).

Description:

Body length 3.0 mm. Habitus as in Fig. 60. Coloration: head blackish; pronotum dark-brown; elytra and abdomen brown; legs yellowish; antennae reddish-yellow.

Head strongly transverse, across eyes approximately 1.25 times as wide as long; eyes large, postocular region practically obsolete ( Fig. 61); punctation coarse and dense, in posterior portion of dorsal surface only slightly sparser than in anterior portion; interstices with very shallow microreticulation (distinctly visible only in posterior portion of head); antenna approximately 0.95 mm long.

Pronotum distinctly convex in cross-section, approximately as wide as long, and approximately 0.8 times as wide as head ( Fig. 61); punctation moderately dense and somewhat less coarse than that of head; midline very narrowly impunctate; interstices without microsculpture and glossy.

Elytra short, approximately 0.65 times as long as, and at posterior margin about as wide as pronotum; humeral angles weakly marked ( Fig. 61); punctation very dense, moderately fine, and rather ill-defined; surface with subdued shine. Hind wings absent.

Abdomen approximately 1.1 times as broad as elytra; punctation fine and moderately dense, sparser on tergite VII than on anterior tergites; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe.

: sternite VII with posterior margin broadly and very shallowly concave in the middle, near this concavity with approximately 10 rather weakly modified dark setae ( Fig. 62); sternite VIII weakly oblong, anteriorly with short elevation (best visible in lateral view) without setae, median portion extensively devoid of pubescence, posterior excision conspicuously narrow, its depth approximately 1/7 the length of sternite ( Figs 63-64); aedeagus with short, relatively stout, laterally compressed, subapically dentate ventral process and with pair of sclerotized structures in internal sac ( Fig. 65).

Etymology:

The specific epithet (Latin, adjective: incised) alludes to the narrow posterior excision of the male sternite VIII.

Comparative notes:

Based on the morphology of the aedeagus (internal structures, shape of the apex of the ventral process), the shape and chaetotaxy of the male sternites VII and VIII, as well as on the punctation and microsculpture of the head, N .. rimatus is closely related to N .. barbatulus and its allies. It is distinguished from all its congeners by the shape of the ventral process of the aedeagus, as well as by the shape and chaetotaxy of the male sternite VIII, particularly the narrow posterior excision. It is separated from many of its congeners also by the short wings and the absence of a palisade fringe at the posterior margin of tergite VII. From the similar and geographically close micropterous N .. rimatus , it is additionally distinguished by the absence of a median furrow on the pronotum, and the much less pronounced microsculpture on the head.

Distribution and bionomics:

The type locality is situated in Guangxi province, southern China. As can be inferred from the adaptive reductions of elytral length, hind wings, and the palisade fringe at the posterior margin of the abdominal tergite VII, the species probably has a restricted distribution. The slightly teneral holotype was collected at an altitude of 1020 m in August .