Neosclerus barbatus, 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 : 98-100

Neosclerus barbatus sp. n. ( Figs 15-20)

Type material:

Holotype : " Thailand, Ban Sai Yok, 9:III:1982, G. de Rougemont / Lobochilus sp. ?, det. 198 [sic], G. de Rougemont / Holotypus  Neosclerus barbatus sp. n. det. V. Assing 2010 " (cAss).

Description:

Body length 3.0 mm. Habitus as in Fig. 15. Coloration: head blackish; pronotum blackish-brown; elytra dark-brown, with the humeral angles and the posterior margin reddish-yellow; abdomen dark-brown with paler apex; legs yellowish; antennae reddish-yellow.

Head across eyes approximately 1.15 times as wide as long; postocular region approximately as long as width of antennomere II in dorsal view ( Fig. 16); punctation very coarse and dense, not distinctly sparser in posterior portion of dorsal surface; interstices without microreticulation and glossy; antenna approximately 0.95 mm long.

Pronotum indistinctly oblong, approximately 1.03 times as wide as long, and approximately 0.85 times as wide as head; punctation as coarse and dense as that of head; impunctate midline ill-defined, reduced to short and narrow patch in posterior half; interstices without microsculpture and glossy ( Fig. 16).

Elytra relatively long and large, 1.03 times as long and approximately 1.15 times as wide as pronotum; humeral angles marked ( Fig. 16); punctation dense and moderately fine; interstices glossy. Hind wings fully developed.

Abdomen distinctly narrower than elytra; punctation fine and moderately dense on anterior tergites, sparser on posterior tergites; interstices with distinct microsculpture; posterior margin of tergite VII with palisade fringe.

: sternite VII with posterior margin moderately concave, near this concavity with cluster of long dark submarginal setae ( Fig. 17); sternite VIII anteriorly unmodified, posterior excision acute,

deep, and V-shaped, its depth approximately 1/4 the length of sternite ( Fig. 18); aedeagus small, barely 0.5 mm long, with long, slender, and apically weakly hooked ventral process, internal sac with two long series of small sclerotized structures ( Figs 19-20).

Etymology:

The specific epithet (Latin, adjective: with beard) alludes to the cluster of setae near the posterior margin of the male sternite VII.

Comparative notes:

Based on the morphology of the aedeagus (ventral process slender in lateral view, not compressed laterally, and apically weakly hooked; internal sac with two long series of small sclerotized structures), the shape and chaetotaxy of the male sternites VII (posterior margin concave in the middle and with cluster of dark setae) and VIII (anteriorly unmodified), N .. barbatus is closely allied to N .. fortepunctatus and N .. dupleseriatus . It is distinguished from all its congeners particularly by the shape of the ventral process of the aedeagus, as well as by the conspicuously coarse and dense punctation of the whole dorsal surface of the head and of the pronotum.

Distribution and bionomics:

The species is currently known only from the type locality in Thailand, where it was collected in March .