Lathrobium jinfoicum, 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 : 39-41

Lathrobium jinfoicum sp. n.

( Figs 65-72 )

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 jinfoicum sp. n., det. V. Assing 2012” (cAss) . Paratypes: 5 : same data as holotype; 2 : “ 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) is derived from the name of the mountain where the species is probably endemic.

Description:

Species of rather small size, without sexual size dimorphism; body length 5.0- 5.8 mm; length of forebody 2.6- 2.8 mm. Habitus as in Fig. 65 . Coloration: body brown to blackish-brown with slightly paler elytra; legs and antennae reddish.

Head ( Fig. 66 ) indistinctly oblong, 1.01-1.05 times as long as broad; punctation moderately coarse and dense, sparser in median dorsal portion; interstices with fine microreticulation. Eyes relatively small, approximately one third as long as postocular region in dorsal view and

composed of approximately 30 ommatidia. Antenna 1.4- 1.5 mm long.

Pronotum ( Fig. 66 ) approximately 1.25 times as long as broad and about 1.05 times as broad as head; punctation similar to that of head; impunctate midline moderately broad; interstices without microsculpture.

Elytra ( Fig. 66 ) short, little more than 0.5 times as long as pronotum; punctation dense, shallow, and weakly defined. Hind wings completely reduced. Protarsi with weakly pronounced sexual dimorphism.

Abdomen with rather fine and dense punctation, that of tergite VII distinctly sparser than that of anterior tergites; microsculpture fine and shallow, interstices rather glossy; posterior margin of tergite VII without palisade fringe; tergite VIII without evident sexual dimorphism, posterior margin obtusely pointed in the middle in both sexes.

: protarsomeres I-IV moderately strongly dilated; sternites III-VI unmodified; sternite VII ( Fig. 67 ) without appreciable modifications; sternite VIII ( Fig. 68 ) oblong, posterior margin convex, with posterior excision in distinctly asymmetric position, margins of this excision with two small, but defined clusters of dense black setae; aedeagus ( Figs 69-70 ) 0.9 mm long, slender, and distinctly asymmetric; ventral process asymmetric, apex of ventral process apparently fused with dorsal plate; internal sac with long and slender sclerotized spine.

: protarsomeres I-IV slightly less dilated than in male; sternite VIII ( Fig. 71 ) 0.85 mm long, oblong, and with strongly convex posterior margin; tergite IX with short undivided median portion and with rather short postero-lateral processes; tergite X flat in cross-section, approximately 3 times as long as tergite IX in the middle ( Fig. 72 ).

Comparative notes:

Lathrobium jinfoicum is readily distinguished from the syntopic L. fortepunctatum by external characters alone, particularly its distinctly smaller size, different coloration, less coarse punctation of the forebody, the more slender head, smaller eyes, more slender pronotum, and the less pronounced sexual dimorphism of the protarsi. In addition, both species are distinguished by the completely different sexual characters. Based on the generally similar external and the possibly synapomorphically derived sexual characters (shape and chaetotaxy of the male sternite VII, the oblong male sternite VIII with unmodified pubescence and convex posterior margin, the slender and asymmetric aedeagus with a long internal spine, the posteriorly strongly convex posterior margin of the female sternite VIII, and the morphology of the female tergites IX and X), L. jinfoicum appears to be closely allied to L. effeminatum ASSING , in press from the Qinling Shan. It is distinguished from this species particularly by the asymmetric posterior excision of the male sternite VIII and by the shape of the aedeagus.

Distribution and natural history:

Like the syntopic L. fortepunctatum , L. jinfoicum is probably endemic to the Jinfo Shan in Chongqing province, where the specimens were collected at altitudes of 1750 and 1800 m.

Figures

Figs 65-79: Lathrobium jinfoicum sp. n. (65-72) and L. imminutum sp. n. (73-79): habitus (65); forebody (66, 73); male sternite VII (67, 74); male sternite VIII (68, 75); aedeagus in lateral and in ventral view (69-70, 76-77); female sternite VIII (71, 79); female tergites IX-X (72); internal structures of aedeagus in lateral view (78). Scale bars: 65-66, 73: 1.0 mm; 67-72, 74-77, 79: 0.5 mm; 78: 0.2 mm.