Lathrobium duplebarbatum, Assing, 2013

Assing, V., 2013, On the Lathrobium fauna of Japan (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 45 (1), pp. 1615-1641 : 1626-1628

Lathrobium duplebarbatum nov.sp. ( Figs 23-28 )

T y p e m a t e r i a l Holotype 3: " JAPAN - Kyushu, Fukuoka pref., Munakata city, Mt. Jouyama , 13.V.2006, leg. T. Lackner / Holotypus 3 Lathrobium duplebarbatum sp.n., det. V. Assing 2013" (cAss).

E t y m o l o g y: The specific epithet (Latin, adjective: double-bearded) refers to the conspicuous pair of clusters of modified black setae at the posterior margin of the male sternite VIII.

D e s c r i p t i o n: Species of moderately large size; body length 8.2 mm; length of forebody 3.7 mm. Habitus as in Fig. 23 . Coloration: forebody blackish except for the diffusely paler posterior margins of the elytra; abdomen blackish-brown; legs reddish, with the profemora weakly infuscate; antennae reddish.

Head ( Fig. 24 ) distinctly transverse, 1.12 times as broad as long, not distinctly dilated posteriad; punctation coarse and moderately dense, sparser in median dorsal portion; interstices with fine and shallow microreticulation. Eyes approximately 0.4 times as long as postocular region in dorsal view, weakly convex, and composed of distinctly more than 50 ommatidia. Antenna 2.2 mm long.

Pronotum ( Fig. 24 ) 1.15 times as long as broad and 1.05 times as broad as head; anterior three fourths of lateral margins weakly tapering posteriad in dorsal view; punctation rather sparse, as coarse as that of head; impunctate median band narrow.

Elytra ( Fig. 24 ) 0.57 times as long as pronotum, not distinctly dilated posteriad; combined posterior margins very weakly concave; punctation rather coarse, defined, and dense, distinctly denser than that of pronotum. Hind wings completely reduced.

Abdomen 1.08 times as broad as elytra; punctation fine and dense, nearly as dense on tergite VII as on anterior tergites; interstices with fine microsculpture and subdued shine; posterior margin of tergite VII without palisade fringe.

3: protarsomeres I-IV moderately dilated; tergite VIII with weakly convex posterior margin; sternites III-VI unmodified; sternite VII ( Fig. 25 ) moderately transverse and with shallowly concave posterior margin, pubescence not distinctly modified; sternite VIII ( Fig. 26 ) transverse and with distinct postero-median impression, this impression without setae in the middle, on either side of impression with conspicuous cluster of distinctly modified stout black setae at posterior margin, posterior excision broad and shallow; aedeagus ( Figs 27-28 ) 1.0 mm long and strongly asymmetric; ventral process short, asymmetric, and excavate along middle, right apex (ventral view) curved, longer and more massive than left apex; dorsal plate with rather weakly sclerotized, distinctly asymmetric, large, long, and apically acute apical portion distinctly exceeding beyond apex of ventral process, and with short curved basal portion; internal sac without sclerotized structures.

♀: unknown.

C o m p a r a t i v e n o t e s: Only five micropterous Lathrobium species had been reported from Kyushu. None of them has a pair of clusters of modified setae at the posterior margin of the male sternite VIII. Only one species, L. nomurai NAKANE 1955 , was previously known from Fukuoka Prefecture. In addition to the unmodified pubescence of the male sternite VIII, it is distinguished from L. duplebarbatum by larger size (14 mm), the reddish-brown coloration of the body, the broader head (broader than pronotum), and the finer punctation of the forebody.

D i s t r i b u t i o n: The type locality is situated on Jô-yama (33°49'N, 130°35'E), a hill little more than 5 km to the northeast of Munakata, Fukuoka-ken, in the extreme north of Kyushu.

Figures

Figs 23-29: Lathrobium duplebarbatum nov.sp. (23-28) and L. imminutum ASSING (29): (23) habitus; (24) forebody; (25) male sternite VII; (26) male sternite VIII; (27-29) aedeagus in lateral and in ventral view. Scale bars: 23-24: 1.0 mm; 25-29: 0.5 mm.