Trichoglossina acutissima, Assing, 2018

Assing, Volker, 2018, Six new species of Trichoglossina from China (Coleoptera: Staphylinidae: Aleocharinae: Oxypodini), Linzer biologische Beiträge 50 (1), pp. 89-109 : 96-97

Trichoglossina acutissima nov.sp. ( Figs 28-36 , 47-50 , Map 1 )

T y p e m a t e r i a l: Holotype ♂: " CHINA [26] - N-Sichuan, N Songpan, 33°15'26''N, 103°46'03''E, 2700 m, spruce forest with birch, 12.VIII.2012, V. Assing / Holotypus ♂ Trichoglossina acutissima sp.n., det. V. Assing 2018" (cAss) . Paratypes: 8♂♂, 11♀♀: same data as holotype (cAss) ; 8 exs.: same data, but leg. Schülke ( MNB, cAss) .

E t y m o l o g y: The specific epithet is the superlative of the Latin adjective acutus and alludes to the acute apex of the ventral process of the aedeagus both in lateral and in ventral view.

D e s c r i p t i o n: Body length 2.8-3.5 mm; length of forebody 1.3-1.5 mm. Habitus as in Fig. 28 . Coloration: head blackish; pronotum brown to blackish with the margins narrowly yellowish to reddish; elytra yellowish to yellowish-brown, mostly with a large lateral, weakly defined infuscate spot; abdomen blackish with the posterior margins of segments III-VI, the posterior portion of segment VII, and segments VIII-X dark- yellowish to yellowish brown; legs with brown femora and yellowish to reddish tibiae and tarsi; antennae dark-brown with the basal 3-4 antennomeres reddish-yellow; maxillary palpi reddish-yellow with the terminal palpomere pale-yellowish.

Head ( Fig. 29 ) approximately as broad as long or weakly oblong; punctation dense and fine, visible only at high magnification; interstices with pronounced microreticulation. Eyes weakly convex, slightly shorter than postocular region. Antenna ( Fig. 30 ) approximately 0.8 mm long; antennomere IV weakly transverse or as long as broad; antennomeres V-X transverse and gradually increasing in width, X only slightly longer than IX, approximately twice as broad as long, and XI large, nearly as long as the combined length of antennomeres VIII-X.

Pronotum ( Fig. 29 ) 1.20-1.25 times as broad as long and 1.35-1.40 times as broad as head, broadest approximately in the middle, strongly convex in cross-section; punctation and microsculpture similar to those of head.

Elytra ( Fig. 29 ) approximately as long as pronotum or slightly shorter; punctation very dense and fine, only slightly more distinct than that of pronotum; interstices with distinct microsculpture. Hind wings of reduced length, less than twice as long as elytra. Tarsi very long and slender; metatarsus nearly as long as metatibia; metatarsomere I approximately as long as the combined length of II-IV.

Abdomen ( Fig. 31 ) slightly narrower than elytra; tergites III-V with very shallow anteri- or impressions; punctation fine and very dense, nearly as dense on tergite VII as on anterior tergites; posterior margin of tergite VII with palisade fringe.

♂: posterior margin of tergite VIII convexly produced in the middle ( Fig. 47 ); sternite VIII ( Fig. 48 ) significantly longer than tergite VIII, posterior margin truncate; median lobe of aedeagus ( Figs 41-42 ) approximately 0.5 mm long; ventral process apically very acute both in lateral and in ventral view; crista apicalis prominent; internal sac with long flagellum; paramere ( Fig. 34 ) approximately 0.75 mm long, apical lobe long, slender, and medially somewhat constricted, approximately half as long as basal portion of paramere.

♀: posterior margin of tergite VIII angularly produced in the middle ( Fig. 49 ); posterior margin of sternite VIII convex, with a conspicuous fringe of stout modified setae ( Fig. 50 ); spermatheca as in Figs 35-36.

C o m p a r a t i v e n o t e s: The shapes of the median lobe of the aedeagus and the spermatheca somewhat resemble those of T. glaciei PACE, 2012 from Gongga Shan and the environs of Kangding (Sichuan). The new species is distinguished from T. glaciei by the presence of distinct microsculpture on the head and pronotum (absent in T. glaciei), finer punctation of the head and the pronotum, and an aedeagus with the ventral process apically much more acute and straight (sinuate in T. glaciei). For illustrations of the primary sexual characters of T. glaciei see PACE (2012).

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 to the north of Songpan in North Sichuan, China ( Map 1 ). The specimens, two of them teneral, were sifted from litter and moss in a spruce forest with birch at an altitude of 2700 m.

Figures

Map 1: Distributions of Trichoglossina aptera (black and white triangles), T. alticola (white triangle), T. acutissima (white circle), T. volans (white circle), T. discolor (black circle), and T. bifida (white diamonds).

Figs 28-36: Trichoglossina acutissima: habitus (28); forebody (29); antenna (30); abdomen (31); median lobe of aedeagus in lateral view (32); apical portion of median lobe in ventral view (33); paramere (34); spermatheca (35-36). Scale bars: 28: 1.0 mm; 29, 31: 0.5 mm; 30: 0.2 mm; 32-36: 0.1 mm.

Figs 47-54: Trichoglossina acutissima (47-50) and T. bifida (51-54): male tergite VIII (47, 51); male sternite VIII (48, 52); female tergite VIII (49); female sternite VIII (50, 54); posterior portion of female tergite VIII (53). Scale bar: 0.2 mm.

Figs 37-46: Trichoglossina bifida: habitus (37); forebody (38); antenna (39); abdomen (40); median lobe of aedeagus in lateral view (41); apical portion of median lobe in ventral view (42); paramere (43); apical lobe of paramere (44); spermatheca (45-46). Scale bars: 37: 1.0 mm; 38, 40: 0.5 mm; 39: 0.2 mm; 41-46: 0.1 mm.