Lathrobium fortepunctatum, 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 : 38-39

Lathrobium fortepunctatum sp. n.

( Figs 57-64 )

Type material:

Holotype : “ CHINA: SE Sichuan Jinfo Shan , 29°01N, 107°14E, 1750 m, 26.VI.1998, A. Smetana [C69] / 1998 China Expedition, J. Farkač, D. Král, J. Schneider & A. Smetana / Holotypus  Lathrobium fortepunctatum sp. n., det. V. Assing 2012” (cAss) . Paratype : “ CHINA: SE Sichuan Jinfo Shan , 29°01N, 107°14E, 1800 m, 27.VI.1998, A. Smetana [C70] / 1998 China Expedition, J. Farkač, D. Král, J. Schneider & A. Smetana ” (cSme) .

Etymology:

The specific epithet (Latin, adjective) refers to the conspicuously coarse and dense punctation of the forebody.

Description:

Species of moderately large size; body length 7.7-8.0 mm; length of forebody 3.9-4.1 mm. Habitus as in Fig. 57 . Coloration: body black; legs and antennae dark-brown.

Head ( Fig. 58 ) transverse, 1.09 times as broad as long in holotype and 1.06 times as broad as long in paratype; punctation conspicuously coarse and dense, somewhat sparser in median dorsal portion; interstices glossy, with very shallow microreticulation. Eyes relatively large, approximately half as long as postocular region in dorsal view and composed of distinctly more than 50 ommatidia. Antenna 1.9-2.1 mm long.

Pronotum ( Fig. 58 ) rather short, approximately 1.2 times as long as broad and 1.08 times as broad as head; punctation similar to that of head; impunctate midline narrow; interstices without microsculpture.

Elytra ( Fig. 58 ) short, 0.53 times as long as pronotum; punctation dense, almost as coarse as that of head and pronotum. Hind wings completely reduced. Protarsi with pronounced sexual dimorphism.

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

: protarsomeres I-IV strongly dilated; posterior margin of tergite VIII weakly convex; sternites III-VI unmodified; sternite VII ( Fig. 59 ) weakly modified, pubescence unmodified, posterior margin weakly concave; sternite VIII ( Fig. 60 ) weakly transverse, strongly modified, slightly asymmetric, median impression pronounced, extensive, and with extremely numerous, extremely short, and conspicuously dense modified short black setae, on either side of the deep, broad, and slightly asymmetric posterior excision with conspicuous cluster of extremely dense and strongly modified, short and stout black setae, the two clusters of different shape and size; aedeagus ( Figs 61-62 ) 1.2 mm long, strongly asymmetric; ventral process strongly asymmetric, with large lateral lamellae, and partly fused with the asymmetric dorsal plate; internal sac without sclerotized structures.

: protarsomeres I-IV distinctly dilated, but less so than in male; posterior margin of tergite VIII obtusely pointed in the middle; sternite VIII ( Fig. 63 ) 1.1 mm long, distinctly oblong, and with strongly convex posterior margin; tergite IX completely separated in the middle and with long postero-lateral processes; tergite X convex in cross-section, reaching anterior margin of tergite IX ( Fig. 64 ).

Comparative notes:

This distinctive species is characterized particularly by its relatively broad and (in cross-section) weakly convex forebody, the conspicuously dense and coarse punctation of the forebody, the conspicuous shape and chaetotaxy of the male sternite VIII, the derived morphology of the strongly asymmetric aedeagus, the shape of the female sternite VIII, and the completely divided female tergite IX. Shared derived characters suggesting closer phylogenetic affiliations with other described species recorded from China were not found. From L. lobrathioides ASSING, 2012 , which, too, was described from the Jinfo Shan, L. fortepunctatum is readily distinguished by the much shorter elytra, smaller and less convex eyes, different coloration, and the completely different sexual characters. For illustrations of L. lobrathioides see ASSING (2012b).

Distribution and natural history: Lathrobium fortepunctatum is most likely endemic to the Jinfo Shan in Chongqing province (province status since 1997). The specimens were collected at altitudes of 1750 and 1800 m.

Figures

Figs 57-64: Lathrobium fortepunctatum sp. n.: habitus (57); forebody (58); male sternite VII (59); male sternite VIII (60); aedeagus in lateral and in ventral view (61-62); female sternite VIII (63); female tergites IX-X (64). Scale bars: 57-58: 1.0 mm; 59-64: 0.5 mm.