Lathrobium kuramaicum, Assing, 2013

Assing, V., 2013, On the Lathrobium fauna of Japan (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 45 (1), pp. 1615-1641 : 1624-1626

Lathrobium kuramaicum nov.sp. ( Figs 17-22 )

T y p e m a t e r i a l Holotype 3: " JAPAN - Honshu, Kyoto env., Kurama-yama , 27.III.2006, leg. T. Lackner / Holotypus 3 Lathrobium kuramaicum sp.n., det. V. Assing 2013" (cAss).

E t y m o l o g y: The specific epithet (adjective) is derived from the name of the mountain (Kurama-yama) where the species was discovered.

D e s c r i p t i o n: Species of moderately large size; body length 7.7 mm; length of forebody 3.6 mm. Habitus as in Fig. 17 . Coloration: head blackish-brown; remainder of body castaneous; legs yellowish-brown; antennae reddish.

Head ( Fig. 18 ) rather large in relation to remainder of body, 1.05 times as broad as long, not distinctly dilated posteriad; punctation moderately coarse and moderately dense, sparser in median dorsal portion; interstices with fine and shallow microreticulation. Eyes approximately one fourth as long as postocular region in dorsal view, flat, and composed of approximately 50 ommatidia. Antenna 2.2 mm long.

Pronotum ( Fig. 18 ) 1.15 times as long as broad and 0.98 times as broad as head; anterior three fourths of lateral margins subparallel in dorsal view; punctation similar to that of head; impunctate median band rather narrow.

Elytra ( Fig. 18 ) 0.56 times as long as pronotum, very weakly dilated posteriad; combined posterior margins very weakly concave; punctation rather fine, shallow, and weakly defined. Hind wings completely reduced.

Abdomen 1.1 times as broad as elytra; punctation fine and dense, nearly as dense on tergite VII as on anterior tergites; interstices with fine and very shallow microsculpture, somewhat glossy; posterior margin of tergite VII without palisade fringe.

3: protarsomeres I-IV strongly dilated; tergite VIII with very weakly convex posterior margin; tergite IX elongated and slender, much longer than broad; sternites III-VI unmodified; sternite VII ( Fig. 19 ) moderately transverse and with shallow postero-median impression, this impression with sparse pubescence, pubescence not distinctly modified; sternite VIII ( Fig. 20 ) approximately as long as broad, posteriorly somewhat produced and with posterior excision of nearly semi-circular shape; aedeagus ( Figs 21 - 22 ) 1.8 mm long and somewhat asymmetric; ventral process conspicuously elongated, very slender and apically acute, weakly curved in lateral view, and slightly asymmetric in ventral view; dorsal plate with conspicuously long, distinctly asymmetric, and apically convex apical portion, and with very 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: The similarly derived male sexual characters suggest that L. kuramaicum is closely allied to L. masumotoi WATANABE 2011 from Nagano Prefecture (Central Honshu) and L. kagaense WATANABE & HOSHINA 2003 from Hakusan, a mountain in southeastern Ishikawa Prefecture (Central Honshu). The new species is distinguished from them as follows:

from L. masumotoi by the relatively larger head, the denser punctation of the pronotum, the posteriorly less distinctly dilated elytra, the less distinctly concave combined posterior margins of the elytra, the much narrower posterior excision of the male sternite VIII, and the morphology of the smaller aedeagus ( L. masumotoi : length of aedeagus 2.1 mm; ventral process strongly laterally compressed, somewhat twisted, and more strongly curved in lateral view; dorsal plate of different shape).

from L. kagaense by the unmodified male sternite VI ( L. kagaense : sternite VI with oblong impression in the middle), the deeper posterior excision of the male sternite VIII, and by the shape of the aedeagus ( L. kagaense : ventral process less slender and somewhat twisted; dorsal plate of different shape).

For illustrations of the male sexual characters of L. masumotoi and L. kagaense see WATANABE (2011) and WATANABE & HOSHINA (2003), respectively.

D i s t r i b u t i o n: The type locality is situated on the Kurama-yama (35°07'N, 130°35'E), a mountain in Kyoto-fu, to the north of Kyoto, in Central Honshu.

Figures

Figs 17-22: Lathrobium kuramaicum nov.sp.: (17) habitus; (18) forebody; (19) male sternite VII; (20) male sternite VIII; (21-22) aedeagus in lateral and in ventral view. Scale bars: 17-18: 1.0 mm; 19-22: 0.5 mm.