Lathrobium plicatum, Assing, 2014

Assing, Volker, 2014, New species and records of Lathrobium from the Palaearctic region, primarily from Nepal (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 64 (1), pp. 1-28 : 23-24

Lathrobium plicatum sp. n.

( Figs 130-137 , Map 2 )

Type material: Holotype : “ NEPAL W Dhaulagiri, env. Dhule , 3400–3500 m, 28°42'10"N, 82°55'53"E, 18.IX.2012, leg. J. Schmidt / Holotypus  Lathrobium plicatum sp. n., det. V. Assing 2013” ( NME).

Paratypes: 1 , 4 : same data as holotype ( NME, cAss) .

Etymology: The specific epithet is the past participle of the Latin verb plicare (to coil up) and alludes to the conspicuous shape of the ventral process of the aedeagus in lateral view.

Description: Body length 5.0– 6.4 mm; length of forebody 2.3–2.7 mm; body size subject to sexual dimorphism, males larger than females. Habitus as in Fig. 130 . Coloration: forebody reddish; abdomen dark-brown; legs dark-yellowish; antennae reddish.

Head ( Fig. 131 ) 1.02–1.07 times as long as broad; punctation sparse and moderately coarse; interstices distinctly broader than diameter of punctures, with extremely shallow, almost obsolete microreticulation. Eyes small, composed of approximately 10 ommatidia, approximately one-sixth as long as postocular region in dorsal view. Antenna 1.3–1.4 mm long.

Pronotum ( Fig. 131 ) approximately 1.25 times as long as broad and 1.00–1.03 times as broad as head; punctation similar to that of head; midline broadly impunctate; interstices without microsculpture.

Elytra ( Fig. 131 ) short, 0.55–0.57 times as long as pronotum; punctation fine and rather sparse; interstices without distinct microsculpture. Hind wings completely reduced. Protarsomeres I–IV with pronounced sexual dimorphism; metatibiae compressed in apical twothirds.

Abdomen slightly broader than elytra; punctation distinct and dense; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe; posterior margin of tergite VIII very weakly convex, nearly truncate.

: protarsomeres I–IV strongly dilated; sternite VII ( Fig. 132 ) distinctly transverse and with very weakly modified pubescence, posterior margin shallowly V-shaped; sternite VIII ( Fig. 133 ) approximately 1.07 times as broad as long, with unmodified pubescence, posterior excision moderately deep and slightly asymmetric, nearly U-shaped; aedeagus ( Figs 134–135 ) approximately 1.4 mm long; ventral process of highly distinctive shape, apically very long and slender, coiled in lateral view; dorsal plate membranous, not sclerotized; internal sac without sclerotized structures.

: protarsomeres I–IV moderately dilated, much less so than in male; sternite VIII ( Fig. 136 ) approximately 1.23 times as long as broad, strongly tapering posteriad and with truncate posterior margin; tergite IX ( Fig. 137 ) undivided in the middle, postero-lateral processes short and apically acute, barely extending beyond apex of tergite X; tergite X ( Fig. 137 ) weakly convex in crosssection, of oval shape, and approximately as long as antero-median portion of tergite IX.

Comparative notes: Like the preceding species, L. plicatum belongs to the L. pectinatum group. It differs from all its congeners particularly by the highly distinctive shape of the ventral process of the aedeagus, also by the shape of the male sternite VII, from most species of the L. pectinatum group additionally by the nearly obsolete microsculpture of the head.

Distribution and natural history: The type locality is situated in the western Dhaulagiri range ( Map 2 ) at an altitude of 3400–3500 m. Most of the type specimens are at least slightly teneral.

Figures

Map 2:Distributions of Lathrobium species inNepal:L. flexaculeatum (white square),L. rectaculeatum (blackstar),L. curvaculeatum (white star), L. hebes (black square), L. imberbe (black triangle), L. plicatum (black diamond), L. calcaratum (circles; white circles: new records; black circle: type locality), L. fodens (white triangles), L. aculeatum (white diamonds).

Figs 130-139: Lathrobium plicatum sp. n. (130-137) and L. ascendens sp. n. (138-139): habitus (130); forebody (131); male sternite VII (132, 138); male sternite VIII (133); aedeagus in lateral and in ventral view (134-135); female sternite VIII (136, 139); female tergites IX-X (137). Scale bars: 130-131: 1.0 mm; 132-139: 0.5 mm.