Masuria (Oncosomechusa) appendiculata, Assing, 2012

Assing, V., 2012, On the taxonomy of Masuria. IV. Four new species from China and Nepal, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 44 (2), pp. 1017-1034 : 1024-1025

Masuria (Oncosomechusa) appendiculata nov.sp. ( Figs 1-9 , Map 1 )

T y p e m a t e r i a l: Holotype: " China: N-Sichuan [CH12-24], pass 35 km NNW Songpan , 32°55'32''N, 103°25'56''E, 3600 m, moist N-slope with Salix and other shrubs, litter, grass roots & moss sifted, 11.VIII.2012, leg. M. Schülke / Holotypus Masuria appendiculata sp. n. det. V. Assing 2012" (cAss) . Paratypes: 14 exs.: same data as holotype (cSch, cAss, OÖLL) ; 1, 7: " China [24] - N-Sichuan, pass NW Songpan , 3600 m, 32°55'32''N, 103°25'56''E, sifted, 11.VIII.2012, V. Assing " (cAss) .

E t y m o l o g y: The specific epithet (Latin, adjective) alludes to the pair of conspicuous appendages at the base of the ventral process of the aedeagus.

D e s c r i p t i o n: Body length 2.0- 2.6 mm; length of forebody 1.0- 1.1 mm. Habitus as in Fig. 1 . Coloration: forebody yellowish-red to reddish, often with the head slightly darker; abdomen dark-brown with the base and the apex reddish to variable extent; legs yellowish; antennae brown to dark-brown, with the basal 2-4 antennomeres reddishyellow.

Head ( Fig. 2 ) distinctly transverse; punctation extremely fine, barely noticeable; interstices with shallow microreticulation; eyes relatively small and weakly projecting from lateral contours of head, shorter than postocular region in dorsal view. Antenna ( Fig. 3 ) 0.85-0.90 mm long, relatively slender and moderately incrassate apically; antennomere III slightly shorter than II; IV weakly oblong, V approximately as wide as long, VI weakly transverse, VI-X of gradually increasing width and increasingly transverse, X less than twice as wide as long.

Pronotum ( Figs 2, 4 ) relatively large and distinctly convex in cross-section, approximately 1.3 times as wide as long and 1.3 times as wide as head; maximal width approximately in the middle; posterior angles rounded, weakly marked; punctation usually extremely fine and shallow, barely noticeable; microsculpture more pronounced than that of head; integument only with subdued shine; pubescence of midline directed caudad.

Elytra ( Fig. 2 ) at posterior margin approximately as broad as pronotum, posteriorly distinctly widened, and very short, 0.50-0.55 times as long as pronotum; punctation slightly more distinct than that of pronotum; microsculpture pronounced, more so than that of pronotum. Hind wings completely reduced. Legs slender; metatarsomere I approximately as long as the combined length of II-IV or slightly shorter.

Abdomen ( Fig. 5 ) broad, widest at segment V; punctation rather dense, fine, but more distinct than that of forebody, somewhat sparser on tergites VII and VIII than on anterior tergites; microsculpture pronounced, more so than that of forebody, particularly on anterior tergites; posterior margin of tergite VII without palisade fringe.

: posterior margin of tergite VIII convex, in the middle sometimes weakly concave; posterior margin of sternite VIII strongly convex; median lobe of aedeagus ( Figs 6-7 ) 0.5 mm long, at base of ventral process with pair of conspicuous appendages.

: tergite VIII of similar shape as that of male; sternite VIII posteriorly produced, in the middle moderately concave and with fringe of long, stout, pale-coloured marginal setae; spermatheca as in Fig. 8.

C o m p a r a t i v e n o t e s: Masuria appendiculata is characterised particularly by the pair of conspicuous appendages at the base of the ventral process of the aedeagus, a character separating it from all other species of the genus. It is additionally distinguished from the geographically close M. schuelkei and M. chinensis by the presence of distinct

microsculpture on the forebody and by the much finer punctation of the head and pronotum.

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 some 35 km to the northwest of Songpan in northern Sichuan ( Map 1 ). The specimens were sifted from leaf litter, grass roots, and moss on a moist subalpine north slope with Salix and other shrubs at an altitude of 3600 m ( Fig. 9 ).

Figures

Map 1: Distribution of Masuria species in China: M. chinensis PACE (white diamond); M. appen- diculata nov.sp. (black triangle); M. schuelkei nov.sp. (white triangle); M. brevipennis ASSING (black circle); M. yunnanica ASSING (white circles); M. subnitens nov.sp. (black diamond); M. daliensis ASSING (white square).

Figs 1-8: Masuria appendiculata nov.sp.: (1) habitus; (2) forebody; (3) antenna; (4) median dorsal portion of pronotum; (5) tergites IV-VI of abdomen; (6) median lobe of aedeagus in lateral view; (7) base of ventral process of median lobe in lateral view; (8) spermatheca. Scale bars: 1: 1.0 mm; 2: 0.5 mm; 3: 0.2 mm; 4-6: 0.1 mm; 7-8: 0.05 mm.

Fig. 9: Type locality of Masuria appendiculata nov.sp..