Echiaster paulexcisus, Assing & I, 2014

Assing, V. & I, North, 2014, Three new species and additional records of Echiaster from Asia (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 46 (2), pp. 1087-1096 : 1092-1093

Echiaster paulexcisus nov.sp.

( Figs 10-13 , Map 1 )

Type material: Holotype: " THAILAND: Chiang Mai, Doi Suthep, 1600 m, 4.XI.1985, Burckhardt-Löbl / Holotypus Echiaster paulexcisus sp.n. det. V. Assing 2014" ( MHNG) . Paratypes: 1, 2: same data as holotype ( MHNG, cAss).

Etymology: The specific epithet is an adjective composed of the Latin adverb paulum (slightly) and the adjective excisus. It refers to the posteriorly shallowly excised male sternite VIII.

Description: Body length 5.0- 5.7 mm; length of forebody 2.6-2.8 mm. Coloration: head and pronotum reddish to dark-brown; elytra dark-brown to blackish, each with a large and defined reddish, subcircular humeral spot; abdomen dark-brown to blackish; legs yellowish; antennae reddish, apically dark-yellowish.

Head ( Fig. 10 ) 1.02-1.06 times as long as broad, widest across eyes, behind eyes convexly narrowed towards neck in dorsal view; posterior angles obsolete; punctation coarse, areolate, and extremely dense; interstices reduced to narrow ridges; dorsal surface matt. Eyes approximately 0.7-0.8 times as long as distance from posterior margin of eye to posterior constriction of head in dorsal view. Antenna 0.8-0.9 mm long.

Pronotum ( Fig. 10 ) slender, 1.35-1.40 times as long as broad and 0.75-0.80 times as broad as head; median portion shallowly impressed in posterior two thirds, this impression with median elevation in posterior third of pronotum; punctation similar to that of head.

Elytra ( Fig. 10 ) short, 0.65-0.70 times as long as pronotum, with somewhat depressed disc; humeral angles moderately pronounced; punctation very dense and granulose. Hind wings not examined, but apparently of reduced length.

Abdomen as broad as, or slightly narrower than elytra, broadest at segment V; tergites III-V with coarse and dense punctation; tergites VI-VIII with dense and fine punctation; posterior margin of tergite VII strongly convex, with palisade fringe; tergite VIII distinctly oblong and with strongly convex posterior margin.

: sternite VIII ( Fig. 11 ) distinctly oblong, posterior excision shallow and broad; aedeagus ( Figs 12-13 ) 0.65 mm long, ventral process basally broad (ventral view), apically semitransparent and strongly bent dorsad in lateral view.

Comparative notes: Based on the male sexual characters, particularly the similar general morphology of the aedeagus, E. paulexcisus is closely allied to E. unicolor , from which it differs by the shallow posterior excision of the male sternite VIII and by the slightly larger aedeagus with a ventral process of different shape (apex basally broader in ventral view, apically membranous, and strongly bent dorsad in lateral view).

Distribution and natural history:The type locality is situated to the west of Chiang Mai, North Thailand ( Map 1 ), at an altitude of 1600 m.

Figures

Map 1: Distribution of Echiaster species in Asia. Echiaster discrepans (white circles); E. bivirgatus (white diamonds); E. maior (white triangles); E. paulexcisus (black diamond); E. unicolor (black circles).

Figs 8-13: Echiaster bivirgatus nov.sp., holotype (8-9) and E. paulexcisus nov.sp. (10-13): (8) male sternite VII; (9, 11) male sternite VIII; (10) forebody; (12) aedeagus in lateral view; (13) apical portion of aedeagus in ventral view. Scale bars: 10: 1.0 mm; 8-9, 11-13: 0.2 mm.