Neosclerus barbatulus, 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 : 107-108

Neosclerus barbatulus sp. n. ( Figs 40-46)

Type material:

Holotype : "W. Thailand: 300 m, Thung Yai Wildlife Sanctuary, 15°28'N - 98°48'E / Tak Province, Umphang District , Song Bae Stream. 18-27.iv.1988. / Evergreen rain forest. M.J.D. Brendell. B.M. 1988-183. / flight interception trap / Lobochilus sp. cf. fortepunctatus , det. 1989, G. de Rougemont / Holotypus  Neosclerus barbatulus sp. n. det. V. Assing 2010 " ( BMNH) . Paratypes: 2 : same data as holotype ( BMNH, cAss); 1 : "Burma, Wetwun, 30.I.1982, de Rougemont" (cRou); 1 , 1 : " Burma, Taunggyi, 1.I.1980, de Rougemont" (cRou, cAss); 5 exs.: " Thailand, r. Kwae Noi, Ban Sai Yok, III.1987, G. de Rougemont (cRou, cAss); 2 : " Myanmar: Mandalay Division, 8 km S Pyin Oo Lwin, 1040 m, 21°58.199'N, 96°25.840'E, Paungdaw vill., 20.10.1998, leg. Schillhammer " ( NHMW, cAss); 3 exs.: " China, Yunnan, Xishuangbanna, 20.I.1993, G. de Rougemont " (cRou, cAss); 1 ex.: " China, Yunnan, Xishuangbanna , 22.I.1993, G. de Rougemont " (cRou) .

Description:

Body length 3.0- 3.7 mm. Forebody as in Fig. 40. Coloration: head blackish-brown to black; pronotum dark-brown to blackish-brown; elytra brown to dark-brown; abdomen dark-brown with dark-reddish apex; legs and antennae yellowish.

Head across eyes approximately 1.15 times as wide as long; eyes large, postocular region approximately as long as width of antennomere II in dorsal view; punctation coarse and dense in anterior portion, sparse and finer in posterior portion of dorsal surface ( Fig. 40); interstices with microreticulation (sometimes very superficial and visible only in posterior portion) and moderately glossy or with subdued shine; antenna approximately 0.9-1.0 mm long.

Pronotum approximately as wide as long or indistinctly transverse, and approximately 0.85 times as wide as head; punctation moderately coarse and moderately dense, distinctly finer than that of anterior portion of head ( Fig. 40); midline moderately broadly impunctate; interstices without microsculpture and glossy.

Elytra long and large, 1.10-1.15 times as long and approximately 1.25 times as wide as pronotum; humeral angles marked ( Fig. 40); punctation dense and moderately fine; interstices glossy. Hind wings fully developed.

Abdomen distinctly narrower than elytra; punctation fine and moderately dense; interstices with shallow microsculpture; posterior margin of tergite VII with palisade fringe.

: sternite VII with posterior margin broadly and shallowly concave, near this concavity with a transverse cluster of somewhat condensed setae ( Fig. 41); sternite VIII anteriorly with elevation (best visible in lateral view), tip of this elevation with a cluster of a few short setae, median portion extensively depressed and without pubescence, posterior excision acute, its depth approximately 1/5 the length of sternite ( Figs 42, 46); aedeagus with long and apically acute ventral process, internal sac basally with pair of distinctly sclerotized structures ( Figs 44-45).

Etymology:

The specific epithet (Latin, adjective derived from barbatula, diminutive of barba = 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 (shape of ventral process, shape of internal structures), the synapomorphically derived shape and chaetotaxy of the male sternites VII and VIII, as well as on the presence of microreticulation on the head, N .. barbatulusbarbatulus is closely allied to N .. inarmatus from Taiwan. It is, however, readily distinguished from this species by the much longer and broader elytra, the fully developed hind wings, the paler coloration of the elytra, the presence of a palisade fringe at the posterior margin of the abdominal tergite VII, as well as by the slightly different shape of the apex of the ventral process and the shape and position of the internal structures of the aedeagus.

Distribution and bionomics:

The species is currently known from two localities in Thailand, three localities in Myanmar, and one in the Chinese province Yunnan, suggesting that it is widespread in the Oriental and southern East Palaearctic regions. The specimens from Thailand were partly collected on the wing in an evergreen forest at an altitude of 300 m, one of the specimens from Myanmar was found at an altitude of 1040 m. The months indicated are January, March, April, and October.