Medon yunnanicus, Assing, 2014

Assing, V., 2014, Three new species and a new species group of Medon from China and Taiwan (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 46 (1), pp. 515-523 : 518-520

Medon yunnanicus nov.sp. ( Figs 8-13 , Map 1 )

T y p e m a t e r i a l: Holotype: " CHINA: Yunnan, Baoshan Pref., Gaoligong Shan, 78 km N Tengchong, 2000 m, 25°44'49''N, 98°33'29''E, cleft with creek and forest remnant, litter & dead wood sifted, 1.IX.2009, leg. M. Schülke [ CH 09-21] / Holotypus Medon yunnanicus sp. n. det. V. Assing 2013 " (cAss). Paratype: same data as holotype (cSch).

E t y m o l o g y: The specific epithet is an adjective derived from Yunnan, the Chinese province where the type locality is situated.

D e s c r i p t i o n: Body length 5.5 mm; length of forebody 3.1-3.2 mm. Habitus as in Fig. 8 . Coloration: head blackish; pronotum and elytra pale-brown to dark-brown, with the humeral angles more or less extensively paler (yellowish-brown); abdomen brown; legs dark-yellowish; antennae reddish-brown, with antennomeres I-II reddish.

Head ( Fig. 9 ) as broad as long or weakly oblong; punctation fine and dense; interstices without microreticulation. Eyes moderately large and weakly convex, approximately 0.8 times as long as postocular region in dorsal view. Antenna 1.7-1.8 mm long.

Pronotum ( Fig. 9 ) 1.02-1.04 times as broad as long and approximately as broad as head; anterior and posterior margins concave in the middle; punctation dense, fine, and granulose; midline with very narrow impunctate longitudinal band.

Elytra ( Fig. 9 ) long and broad, nearly 1.2 times as long as pronotum; punctation fine, very dense, and weakly granulose. Hind wings fully developed. Metatarsomere I distinctly longer than II.

Abdomen distinctly narrower than elytra; punctation extremely fine and dense; tergites III-VI with shallow, tergites VII-VIII with pronounced microreticulation; posterior margin of tergite VII with palisade fringe.

: sternite VII ( Fig. 10 ) with large and moderately deep posterior excision, margin of this excision furnished with a distinct comb of numerous palisade setae and with an additional row of long black setae; sternite VIII ( Fig. 11 ) small in relation to sternite VII, transverse, and with shallow median impression, this impression with fine depressed pubescence and with some longer black setae, posterior excision deeply and broadly Vshaped; aedeagus ( Figs 12-13 ) 0.98 mm long; ventral process basally abruptly curved in lateral view and apically notched in ventral view, apically with pair of ventral carinae; internal sac with numerous dark structures.

C o m p a r a t i v e n o t e s: This species is characterized particularly by the distinctive shapes and chaetotaxy of the male sternites VII and VIII, as well as by the morphology of the aedeagus. It differs from the evidently closely related M. profundus by slightly larger body size, the absence of microsculpture on the head, the presence of a narrow impunctate band along the midline of the pronotum, the less deep posterior excision of the male sternite VII, the pubescent median impression and the V-shaped posterior excision of the male sternite VIII, and by the morphology of the larger aedeagus (shape of ventral process both in lateral and in ventral 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 locality is situated in the Gaoligong Shan, Yunnan, China ( Map 1 ). The specimens were sifted from leaf litter in a stream valley at an altitude of 2000 m.

Figures

Map 1: Distributions of the species of the Medon profundus group in China and Taiwan: Medon profundus nov.sp. (circles), M. yunnanicus nov.sp. (triangle), and M. alesi nov.sp. (diamonds).

Figs 8-13: Medon yunnanicus nov.sp.: (8) habitus; (9) forebody; (10) male sternite VII; (11) male sternite VIII; (12-13) aedeagus in lateral and in ventral view. Scale bars: 8-9: 1.0 mm; 10-13: 0.2 mm.