Lathrobium appendiculatum, Assing, 2013

Assing, Volker, 2013, On the Lathrobium fauna of China III. New species and additional records from various provinces (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 63 (1), pp. 25-52 : 37

Lathrobium appendiculatum sp. n.

( Figs 52-56 )

Type material:

Holotype : “ CHINA - S Sichuan, 3000 m, pass N of Jinyang, Rhododendron , primary coniferous forest, 15-19. VI.2004, leg. R. Fabbri / Holotypus  Lathrobium appendiculatum sp. n., det. V. Assing 2012” (cAss).

Etymology:

The specific epithet (Latin, adjective) refers to the conspicuous lateral process of the aedeagus.

Description:

Species of moderately large size. Body length 8.8 mm; length of forebody 4.4 mm. Habitus as in Fig. 52 . Coloration: head, pronotum, and abdomen blackish-brown; elytra blackish-brown with the suture, the posterior and the anterior margins dark-reddish; legs and antennae reddish.

Head ( Fig. 53 ) as broad as long; punctation moderately coarse and moderately dense, sparser in median dorsal portion; interstices with distinct microreticulation. Eyes weakly convex, rather large, nearly half the length of postocular region in dorsal view and composed of> 50 ommatidia. Antenna 2.4 mm long.

Pronotum ( Fig. 53 ) rather broad, 1.22 times as long as broad and 1.04 times as broad as head; punctation similar to that of head, but somewhat coarser; impunctate midline moderately broad; interstices without microsculpture.

Elytra ( Fig. 53 ) moderately short, 0.58 times as long as pronotum; punctation shallow and moderately dense. Hind wings completely reduced.

Abdomen with rather fine and moderately dense punctation, that of tergite VII noticeably sparser than that of anterior tergites; interstices with very shallow microsculpture, rather glossy; posterior margin of tergite VII without palisade fringe.

: protarsomeres I-IV strongly dilated; tergite VIII with distinctly convex posterior margin; sternites III-VI unmodified; sternite VII ( Fig. 54 ) distinctly transverse, symmetric, with shallow postero-median impression, pubescence not distinctly modified, posterior margin broadly and very weakly concave; sternite VIII ( Fig. 55 ) symmetric, weakly transverse, with extensive median impression, with pair of conspicuous clusters of extremely dense modified black setae posteriorly, and with broadly concave posterior margin; aedeagus ( Fig. 56 ) 1.55 mm long, strongly asymmetric and strongly derived; ventral process asymmetric, with conspicuous lateral process, dorso-ventrally compressed, and apically somewhat truncate; dorsal plate with lamellate apical portion of asymmetrically triangular shape; internal sac with long and straight sclerotized spine.

: unknown.

Comparative notes:

Lathrobium appendiculatum is readily identified based on the conspicuous shape and chaetotaxy of the male sternite VIII and on the derived morphology of the aedeagus. Closer affiliations to any of the described Lathrobium species from China are not evident.

Distribution and natural history: The type locality is situated to the north of Jinyang, southern Sichuan, not far from the border with Yunnan. The slightly teneral holotype was collected in a primary coniferous forest at an altitude of 3000 m.

Figures

Figs 44-56: Lathrobium aspinosum sp. n. (44-51) and L. appendiculatum sp. n. (52-56): habitus (44, 52); forebody (45, 53); male sternite VII (46, 54); male sternite VIII (47, 55); aedeagus in lateral view (48); apical portion of aedeagus in ventral view (49); female sternite VIII (50); female tergites IX-X (51); aedeagus in latero-ventral view (56). Scale bars: 44-45, 52-53: 1.0 mm; 46-51, 54-56: 0.5 mm.