Medon profundus, 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 : 516-518

Medon profundus nov.sp. ( Figs 1-7 , Map 1 )

T y p e m a t e r i a l: Holotype: " CHINA (border Shaanxi-Sichuan) [now border Shaanxi- Chongqing], Daba Shan , 20 km SSE Zhenping, 1700-1800 m, 31°44'N, 109°35'E (small creek vall., young dry mixed forest, leaf-litt., moss sifted) 9.& 12.VII.2001 Wrase [07] / Holotypus Medon profundus sp.n. det. V. Assing 2013 " (cAss) . Paratypes: 1: " CHINA: Border Shaanxi - Sichuan [today border Shaanxi-Chongqing] ( Daba Shan ), pass 20 km SSE Zhenping, 1700-1800 m, 31°44'N, 109°35'E, 9.VII.2001, leg. M. Schülke [C01-07] / young dry mixed forest, field edge, small creek valley, moss (sifted) [C01-07]" (cSch); 1, 1: "P. R. China, Sichuan, Emei Shan, N 29°33.6', E103°20.6', 27.vi.-5.vii.2009, 1800-2400 m, sifting11-17, V. Grebennikov " ( CAS, cAss) .

Etymology: The specific epithet (Latin, adjective: deep) alludes to the profound posterior excision of the male sternite VII.

D e s c r i p t i o n: Body length 4.7-5.7 mm; length of forebody 2.6-3.0 mm. Habitus as in Fig. 1 . Coloration: head blackish; pronotum brown; elytra dark yellowish-brown; abdomen dark-brown; legs dark-yellowish; antennae reddish to dark-brown.

Head ( Fig. 2 ) approximately as broad as long; punctation fine and dense; interstices with shallow microreticulation. Eyes large and rather weakly convex, 0.8-1.0 times as long as postocular region in dorsal view. Antenna 1.6-1.8 mm long.

Pronotum ( Fig. 2 ) approximately 1.05 times as broad as long and 0.96-0.98 times as broad as head; anterior and posterior margins concave in the middle; punctation dense, fine (though less so than head), and granulose; midline without impunctate longitudinal band.

Elytra ( Fig. 2 ) long and broad, approximately 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 slightly narrower than elytra; punctation extremely fine and dense; interstices with shallow microreticulation; posterior margin of tergite VII with palisade fringe.

: sternite VII ( Fig. 3 ) with large and profound posterior excision, margin of this excision furnished with a distinct comb of numerous long palisade setae and with an additional row of long black setae ( Fig. 4 ); sternite VIII ( Fig. 5 ) small in relation to sternite VII, transverse, and with median impression, this impression without setae, but enframed by some long black setae, posterior excision deep and broad; aedeagus ( Figs 6- 7 ) approximately 0.9 mm long; ventral process basally distinctly angled in lateral view, apically with ventral carinae and with median furrow; internal sac with numerous dark structures.

C o m p a r a t i v e n o t e s: Together with the two other species described below, M. profundus forms a distinct species group, hereafter referred to as the M. profundus group, characterized among Palaearctic Medon by the fine punctation of the forebody (general appearance somewhat resembling species of Lithocharis DEJEAN 1833), the granulose punctation of the pronotum, the deep posterior excision of the male sternite VII with an uninterrupted comb of numerous long palisade setae, the deep and broad posterior excision of the male sternite VIII, and by the morphology of the aedeagus (ventral process distinctly separated from the aedeagal capsule, basally either abruptly curved or distinctly angled, and ventrally with carinae; internal sac with numerous dark structures). The granulose punctation of the pronotum, the modifications of the male sternites VII and VIII, as well as the derived morphology of the aedeagus evidently represent synapomorphies and leave no doubt that the M. profundus group is monophyletic. For characters distinguishing M. profundus from the two species described below see the comparative notes in the following sections.

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 species is currently known from two localities in China, one in the Daba Shan (Shaanxi / Chongqing) and one in the Emei Shan (Sichuan) ( Map 1 ). The specimens were collected at altitudes between 1700 and 2400 m, those from the Daba Shan were sifted from leaf litter and moss in a young dry mixed forest.

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 1-7: Medon profundus nov.sp.: (1) habitus; (2) forebody; (3) male sternite VII; (4) posterior excision of male sternite VII; (5) male sternite VIII; (6-7) aedeagus in lateral and in ventral view. Scale bars: 1-2: 1.0 mm; 3-7: 0.2 mm.