Tetrabothrus nilgiricus, Assing, 2016

Assing, Volker, 2016, On some Lomechusini of the Palaearctic and Oriental regions (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 66 (1), pp. 13-111 : 94-95

Tetrabothrus nilgiricus spec. nov.

( Figs 152–153 , 435–436 )

Type material: Holotype ♂ [in rather poor condition; most of antennae, left hind leg and right metatarsus missing]: “ S India ; Tamil Nadu ; Nilgiri Hills , 11 km SE Kotagiri; 1000± 100 m; 11°24'N 76°56'E; Kunchappanai, P. Pacholátko leg.; 3.–15.v.2002 / Holotypus ♂ Tetrabothrus nilgiricus sp. n., det. V. Assing 2015” ( NHMB).

Comment: The specific epithet is an adjective derived from Nilgiri Hills, the mountain range where the type locality is situated.

Description: Small species species; body length 4.6 mm; length of forebody 1.9 mm. Coloration: head and pronotum dark-brown; elytra brown; abdomen dark-brown, with the apex (segments VII–X) and the posterior margins of tergites III–VI dark-reddish; legs yellowish, with the apices of the meso- and metafemora infuscate; antennomeres I–V blackish-brown (remainder of antennae missing); maxillary palpi dark-yellowish with yellowish terminal palpomere.

Head ( Fig. 152 ) distinctly transverse, extensively impunctate along middle; punctation in lateral dorsal portions very fine and sparse. Eyes large, approximately 0.7 times as long as distance from posterior margin of eye to posterior constriction of head.

Pronotum ( Fig. 152 ) 1.14 times as broad as long and 1.08 times as broad as head, strongly convex in crosssection; punctation very fine and sparse.

Elytra ( Fig. 152 ) as long as pronotum; punctation very fine and sparse. Hind wings fully developed.

Abdomen ( Fig. 153 ) narrower than elytra and with rather deep anterior impressions on tergites III–VI; tergites III– VI with a lateral seta and two postero-lateral setae (at posterior margin) on either side, otherwise impunctate; tergite VII with three lateral setae on either side; tergite VIII with rather numerous setae at and near posterior margin; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII weakly concave in the middle.

♂: median lobe of aedeagus ( Figs 435–436 ) 0.57 mm long; ventral process strongly curved, apically acute and very slender; paramere 0.6 mm long, its apical lobe of moderate length and slender.

Comparative notes: Tetrabothrus nilgiricus is distinguished from T. indicus , its geographically closest congener, by distinctly smaller size ( T. indicus : length of forebody 2.0– 2.4 mm), darker coloration ( T. indicus : head and pronotum pale-reddish to reddish-brown; elytra pale reddish with the postero-lateral portions more or less distinctly darker; antennae with at least antennomeres I–III reddish), the different punctation pattern of the pronotum ( T. indicus : posterior margins of tergites III–VI each with four postero-lateral setae on either side), and by the shapes of the ventral process and of the crista apicalis of the aedeagus.

Distribution: The type locality is situated in the Nilgiri Hills, Tamil Nadu, South India. The holotype was collected at an altitude of approximately 1000 m.

Figures

Figs 144–159. Amaurodera thailandensis (144–145), A. fasciata (146), A. meorum (147), A. spinans (148), A. varicollis (149), A. disparicollis, male (150), A. disparicollis, female (151), Tetrabothrus nilgiricus (152–153), T. pubescens, syntype (154–156), T. collucatus (157–158), and T. neoguineensis, holotype (159): forebody (144–152, 154, 157, 159); abdomen (153, 156); antenna (155, 158). Scale bars: 144–154, 156–157, 159: 1.0 mm; 155, 158: 0.5 mm.

Figs 420–441. Amaurodera meorum (420–422), A. disparicollis (423–429), A. spinans (430–431), A. varicollis (432–434), Tetrabothrus nilgiricus (435–436), T. indicus (437–439; 439: lectotype), andT. inflexus fromLaos (440–441): spermatheca (420–422, 429, 434); male pronotum (423–424); female pronotum (425–426); median lobe of aedeagus in lateral and in ventral view (427–428, 430–433, 435–437, 440); ventral process of aedeagus (438–439, 441). Scale bars: 423–426: 1.0 mm; 420–422, 427–441: 0.2 mm.