A new species and additional records of Rugilus Leach from Qinling, China (Coleoptera, Staphylinidae, Paederinae)

Abstract A new species of Rugilus Leach, Rugilus (Rugilus) huanghaoi sp. n. from Qinling, Shaanxi Province, China, is described and illustrated. Additional records of seven species from Qinling are reported.


Introduction
According to a series of revisions of the genus Rugilus Leach from Palaearctic and Oriental regions (Assing 2012a(Assing , 2012b(Assing , 2013(Assing , 2014(Assing , 2015, 32 species of the genus have been recorded from China, 25 of them are placed in the nominotypical subgenus, and seven in the subgenus Eurystilicus Fagel. Seven species have been report fromed the Qinling Shan, one of the most diverse areas in China: R.  gemont, 1998, and R. (R.) reticulatus Assing, 2012. During several recent field trips to this region conducted by the authors and their colleagues, all known and an additional new species were collected.

Material and methods
The type material listed in the present study is deposited in the Insect Collection of Shanghai Normal University, Shanghai, P. R. China (SNUC).
The dissected body parts were mounted in Euparal on plastic slides. The habitus photos were taken using a Canon 7D camera. The photos of the sternites and aedeagi were taken using a Canon G9 camera mounted on an Olympus CX31 microscope.

Measurements:
Body length: measured from the anterior margin of the labrum to the apex of the abdomen. Length of forebody: measured from anterior margin of the labrum to the posterior margin of the elytra. Eye length: longitudinal length of eye in dorsal view. Postocular length: measured from posterior margin of eye to posterior constriction of head. Head width: width of head across (and including) eyes. Head length: measured from the clypeal anterior margin to head base. Pronotum width: maximal width of pronotum. Pronotum length: measured in midline from front margin to posterior margin. Width of elytra: combined width of elytra at posterior margin. Length of elytra: measured from apex of scutellum to posterior margin.  (Fig. 1) dark brown; lateral margins of elytra widely yellowish brown; legs and antennae reddish brown. Head (Fig. 2) 0.96-0.97 times as long as wide; punctation umbilicate, very dense, rather coarse and partly confluent, interstices reduced to very narrow ridges; without microsculpture. Eyes large and convex; approximately 0.8-0.9 times as long as pos-  (1, 2), 0.25 mm (3-7). tocular portion. Anterior margin of labrum with two pronounced teeth on either side of the median incision. Pronotum (Fig. 2) 1.16-1.17 times as long as wide, 0.75-0.77 times as broad and 0.92-0.94 times as long as head; punctation similar to that of head; midline with narrow and short impunctate elevation in posterior half; interstices without microsculpture. Elytra (Fig. 2) 0.90-0.98 times as long as wide, 1.13-1.26 times as long and 1.47-1.52 times as broad as pronotum; punctation dense, distinctly finer than that of head and pronotum; interstices without microsculpture.

Description of new species
Abdomen narrower than elytra; tergites III-VI with transverse impressions anteriorly. Punctation of these impressions coarse and dense; punctation of remaining surfaces fine and dense; interstices with distinct microsculpture (Fig. 7); posterior margin of tergite VII with distinct palisade fringe.
Male. Sternite VII (Fig. 3) with broad and trapezoidal excision in the middle of posterior margin; on either side of this excision with a tuft of long black setae. Sternite VIII (Fig. 4) with triangular excision posteriorly. Aedeagus (Figs 5, 6) long and narrow; ventral process widest near middle and gradually narrowed apically in ventral view; abruptly narrowed and slightly curved ventrally in apical third in lateral view.
Comparative notes. Based on the similar external characters, especially the bicoloured elytra and the male sexual characters, the new species is most similar to R. morvani (Rougemont, 1987) from Nepal, from which it is distinguished by the deeper excision of the male sternite VII, with a more prominently produced centre, longer and denser setae on either side of the excision, and by the longer and narrower apical