Lathrobium flexaculeatum, 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 : 16-18

Lathrobium flexaculeatum sp. n.

( Figs 79–88 , Map 2 )

Type material: Holotype : “ NEPAL SW Dhaulagiri, E Dhorpatan 3000 m, 22.IX.12 lg. J. Schmidt, 28°30'08"N, 83°07'45"E / Holotypus  Lathrobium flexaculeatum sp. n., det. V. Assing 2013” ( NME).

Paratypes: 1 , 1 sex? [posterior portion of abdomen missing]: same data as holotype ( NME, cAss) .

Etymology: The specific epithet is an adjective composed of the Latin adjectives flexus (bent) and aculeatus (with a sting). It alludes to the curved sting-shaped apex of the ventral process of the aedeagus.

Description: Body length 5.4–5.6 mm; length of forebody 2.6–2.8 mm. Habitus as in Fig. 79 . Coloration: forebody reddish to dark-brown; abdomen dark-brown to blackish-brown; legs and antennae reddish.

Head ( Fig. 80 ) weakly oblong, approximately 1.04 times as long as broad; punctation moderately dense and moderately coarse, sparser in median dorsal portion; interstices with distinct microreticulation. Eyes small, composed of approximately 10 ommatidia, one-sixth to one-fifth as long as postocular region in dorsal view. Antenna 1.3–1.4 mm long.

Pronotum ( Fig. 80 ) approximately 1.25 times as long as broad and about as broad as head; punctation similar to that of head; midline broadly impunctate; interstices without microsculpture.

Elytra ( Fig. 80 ) approximately 0.6 times as long as pronotum; punctation fine and sparse; interstices without distinct microsculpture. Hind wings completely reduced. Protarsomeres I–IV with weakly pronounced sexual dimorphism; metatibia compressed in apical two-thirds in both sexes; metafemora sexually dimorphic.

Abdomen slightly broader than elytra; punctation distinct and moderately dense; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe.

: protarsomeres I–IV strongly dilated; metafemur posteriorly with a long and oblique (more pronounced basally than apically) carina in the middle ( Fig. 81 ); sternite VII ( Fig. 82 ) strongly transverse, in posterior portion with extensive cluster of numerous long and stout black setae, posterior margin with broad and not very deep posterior excision, margin of this excision with a comb of approximately 35 long palisade setae; sternite VIII ( Fig. 83 ) approximately 1.15 times as broad as long, in antero-median portion extensively without pubescence, posterior excision moderately deep, moderately broad, and anteriorly rounded, lateral margins of this excision with a row of dense short setae; aedeagus ( Figs 84–85 ) approximately 0.95 mm long and somewhat asymmetric; ventral process basally broad and apically extending into a sinuate spine-shaped process in ventral view; dorsal plate broad, short, and apically weakly convex ( Fig. 86 ); internal sac without appreciable structures.

: protarsomeres I–IV moderately dilated; sternite VIII ( Fig. 87 ) 1.13 times as long as broad and with strongly convex posterior margin; tergite IX ( Fig. 88 ) undivided in the middle, postero-lateral processes short, only slightly extending beyond apex of tergite X; tergite X ( Fig. 88 ) flat, of oval shape, and approximately 1.2 times as long as antero-median portion of tergite IX.

Comparative notes: Among the species of the L. pectinatum group, L. flexaculeatum is characterized by the compressed metatibiae (in male and females), the modifications of the male metafemora, the shapes and chaetotaxy of the male sternites VII and VIII, and by the morphology of the aedeagus.

Distribution and natural history: The type locality is situated in the southwestern Dhaulagiri range, Central Nepal ( Map 2 ), at an altitude of 3000 m.

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 79–96: Lathrobium flexaculeatum sp. n. (79–88), L. rectaculeatum sp. n. (89–95), and L. kemum sp. n. (96): male habitus (79, 89); forebody (80, 90); male metafemur (81); male sternite VII (82, 92); male sternite VIII (83, 93); aedeagus in lateral and in ventral view (84–85, 94–95); dorsal plate of aedeagus in dorsal view (86); female sternite VIII (87, 96); female tergites IX–X (88); metatibia (91). Scale bars: 79–80, 89–90: 1.0 mm; 81–85, 87–88, 91–96: 0.5 mm; 86: 0.2 mm.