Drepasiagonusa angulata, Assing, 2018

Assing, Volker, 2018, New species and additional records of Cephalocousya and Drepasiagonusa from China and Russia (Coleoptera: Staphylinidae: Aleocharinae: Oxypodini), Linzer biologische Beiträge 50 (1), pp. 75-88 : 85-86

Drepasiagonusa angulata nov.sp. ( Figs 22-32 )

T y p e m a t e r i a l: Holotype ♂: " CHINA: Qinghai Prov. [CH11-19], road 301 km 180, 43 km ESE Men Yuan , 37°09'32.6''N, 102°02'06.0''E, 2704 m, creek valley with Picea, Salix, Populus, Betula, litter and moss sifted, 5.VII.2011, leg. M. Schülke / Holotypus ♂ Drepasiagonusa angulata sp. n., det. V. Assing 2018" (MNB) . Paratypes: 1♂, 1♀: same data as holotype (MNB, cAss) ; 1♀: " CHINA: Gansu Prov. [CH11-13b], Lenglong Ling Mts., 80 km NNW Honggu, 37°03'47.0''N, 102°39'32.6''E, 3439 m, alpine pasture with Rhododendron and Azalea , litter sifted, 1.VII.2011, leg. M. Schülke " (MNB); 2♀♀: " CHINA: Qinghai Prov. [CH11-11], Lang Shi Dang Jing Qu ( Park ), 75 km NW Honggu, 2896 m, 36°54'08.8''N, 102°21'16.9''E, creek valley on overgrown scree, Populus and Betula forest , litter sifted between rocks, 28.VI.2011, leg. M. Schülke (MNB, cAss) .

E t y m o l o g y: The specific epithet (Latin, adjective) alludes to the angled ventral process of the aedeagus (lateral view).

D e s c r i p t i o n: Body length 2.9-3.6 mm; length of forebody 1.4-1.7 mm. Habitus as in Fig. 22 . Coloration: body black with the elytra usually slightly paler (dark-brown to blackish-brown); legs dark-brown with the tarsi dark-yellowish to pale-brown; antennae dark-brown to blackish-brown with the basal 2-3 antennomeres dark-yellowish to palebrown; maxillary palpi brown to dark-brown with the terminal palpomere yellowish.

Head ( Fig. 23 ) 1.06-1.09 times as broad as long, slightly wedge-shaped (i.e., slightly dilated posteriad); punctation rather dense and very fine, visible only at higher magnification; interstices with pronounced microreticulation and rather matt. Eyes moderately convex and slightly shorter than postocular region in dorsal view. Antenna ( Fig. 24 ) 0.8- 0.9 mm long; antennomere IV approximately as long as broad or weakly oblong; antennomeres V-X weakly transverse and gradually, weakly increasing in width, X approximately 1.5 times as broad as long.

Pronotum ( Fig. 23 ) 1.30-1.35 times as broad as long and 1.20-1.25 times as broad as head, broadest in, or anterior to middle; punctation and microsculpture similar to those of head.

Elytra ( Fig. 23 ) approximately as long as pronotum; punctation dense, much more distinct than that of head and pronotum, but somewhat ill-defined; interstices with shallow microsculpture. Hind wings fully developed. Metatarsomere I approximately as long as the combined length of metatarsomeres III and IV.

Abdomen ( Fig. 25 ) as broad as, or slightly narrower than elytra; tergites III-V with moderately deep anterior impressions, tergite VI without anterior impression; punctation fine and rather dense on tergites III-VI, somewhat sparser on tergite VII; interstices with shallow microreticulation; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII truncate or weakly concave in the middle ( Fig. 26 ).

♂: posterior margin of sternite VIII convexly produced in the middle ( Fig. 27 ); median lobe of aedeagus ( Figs 28-29 ) approximately 0.4 mm long; ventral process somewhat angled in lateral view.

♀: sternite VIII ( Fig. 30 ) with convex posterior margin; spermatheca ( Figs 31-32 ) with long and nearly straight proximal portion.

C o m p a r a t i v e n o t e s: In external characters (coloration, habitus, size, punctation, microsculpture), D. angulata is similar to D. tibetica . It differs from this species by usually slightly paler elytra, a more transverse pronotum, and particularly by the shape of the median lobe of the aedeagus (lateral view).

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 specimens were collected in three localities in Qinghai and Gansu provinces. They were sifted from litter and moss in forests with birch and poplar and in an alpine pasture with rhododendron at altitudes of 2700-3340 m.

Figures

Figs 22-32: Drepasiagonusa angulata: habitus (22); forebody (23); antenna (24); abdomen (25); male tergite VIII (26); male sternite VIII (27); median lobe of aedeagus in lateral view (28-29); female sternite VIII (30); spermatheca (31-32). Scale bars: 22: 1.0 mm; 23, 25: 0.5 mm; 24, 26-27, 30: 0.2 mm; 28-29, 31-32: 0.1 mm.