Tetrabothrus rubricollis, Assing, 2015

Assing, Volker, 2015, On the Tetrabothrus fauna of China (Coleoptera: Staphylinidae: Aleocharinae: Lomechusini), Linzer biologische Beiträge 47 (1), pp. 127-143 : 138-140

Tetrabothrus rubricollis nov.sp. ( Figs 24-28 , Map 1 )

T y p e m a t e r i a l: Holotype ♀: " CHINA [27a] - S-Shaanxi [recte: Sichuan], Micang Shan , 42 km S Hanzhong, 32°40'52''N, 106°49'16''E, 1090 m, 14.VIII.2012, V. Assing / Holotypus ♀ Tetrabothrus rubricollis sp. n., det. V. Assing 2015" (cAss).

E t y m o l o g y: The specific epithet (Latin, adjective) alludes to the reddish pronotum.

D e s c r i p t i o n: Body length 6.5 mm; length of forebody 2.8 mm. Coloration distinctive: head blackish with the clypeus and the mouthparts reddish; pronotum palereddish; elytra blackish; abdomen blackish, with the posterior margins of the segments narrowly reddish; legs yellowish; antennae reddish, with antennomere I infuscate.

Head ( Fig. 24 ) strongly transverse, 1.37 times as broad as long; posterior angles completely obsolete, posterior margin between posterior margin of eye and posterior constriction of head nearly straight; punctation extremely fine and very sparse; pubescence whitish and suberect; microsculpture absent. Eyes very large and bulging, much longer than distance from posterior margin of eye to posterior constriction in dorsal view. Antenna 1.5 mm long, shaped as in Fig. 25 .

Pronotum ( Fig. 24 ) transverse, 1.1 times as broad as long and 1.03 times as broad as head, broadest in the middle, narrowly margined; lateral margins straight in dorsal view; posterior angles rounded, but noticeable; anterior angles both visible in dorsal view; punctation sparse and very fine; midline broadly impuncate; pubescence withish and suberect; microsculpture absent.

Elytra ( Fig. 24 ) approximately 0.9 times as long as pronotum; suture strongly gaping posteriorly; punctation fine and relatively dense; pubescence whitish, conspicuously long, suberect, and rather dense; interstices without microsculpture. Hind wings present. Legs long; metatibia 1.28 mm long; metatarsus 0.67 times as long as metatibia; metatarsomere I approximately as long as the combined length of II and III.

Abdomen ( Fig. 26 ) narrower than elytra, broadest at tergite IV; tergites III-VI with moderately deep anterior impressions, the impression of tergite VI distinctly less deep than that of tergite V; tergites III-VII without microsculpture and impunctate except for few punctures bearing long dark setae at the posterior margins; tergite VIII ( Fig. 27 ) strongly transverse and with truncate posterior margin, with pubescence in posterior half; posterior margin of tergite VII with palisade fringe.

Ƌ: unknown.

♀: sternite VIII ( Fig. 28 ) strongly transverse, posterior margin convex, in the middle truncate.

C o m p a r a t i v e n o t e s: Tetrabothrus rubricollis is distinguished from all its congeners recorded from China by several external characters alone, particularly the coloration, the more strongly transverse head, the much larger eyes, the parallel lateral margins of the pronotum, the broad abdomen, the shallower anterior impression of the abdominal tergite VI, the more numerous long setae in the posterior portion of the abdominal tergite VII, the more extensive pubescence in the posterior portion of the more transverse tergite VIII, and the more transverse female sternite VIII. Based on the similar external characters (head shape, eye size, chaetotaxy of the elytra, broad abdomen with shallow anterior impressions on tergites III-VI), T. rubricollis is closely allied to T. japonicus NAKANE, 1991 ( Japan, South Korea). It differs from this species by the coloration alone ( T. japonicus : head dark-reddish; elytra and abdomen reddish). For illustrations of T. japonicus see MARUYAMA & KISHIMOTO (1999). The only other species with a reddish pronotum in the northern Oriental region is T. vietnamiculus PACE, 2013 , which is distinguished from T. rubricollis by a yellowish-red forebody, smaller body size, and probably numerous additional characters, which are not indicated in the meagre original description ( PACE 2013a).

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: The type locality is situated in the Micang Shan, Sichuan, close to the border with Shaanxi ( Map 1 ). The holotype was collected by tearing out the roots herbaceous vegation on sandy soil near a forest margin at an altitude of 1090 m.

Figures

Map 1: Distributions of Tetrabothrus species in China: T. puetzi (open triangle); T. inflexus (open circles); T. brevalatus (open star); T. cavus (filled circles); T. rubricollis (open diamond); T. chinensis (filled triangle).

Figs 24-28: Tetrabothrus rubricollis nov.sp.: forebody (24); antenna (25); abdomen (26); female tergite VIII (27); female sternite VIII (28). Scale bars: 24, 26: 1.0 mm; 25, 27-28: 0.5 mm.