A new species of genus Tetrasticta Kraatz (Coleoptera, Staphylinidae, Aleocharinae) from Xishuangbanna, Southwest China

Abstract Tetrasticta bobbii Zheng & Zhao, sp. n., collected in Nangongshan, Xishuangbanna, Yunnan, is described and illustrated.


Introduction
The aleocharine genus Tetrasticta Kraatz, 1857 (Aleocharini) contains 13 species worldwide (Maruyama and Sugaya 2002;Maruyama 2004;Pace 2000Pace , 2008Pace , 2013bYamamoto and Maruyama 2013). Pace (2010) synonymized Creochara Cameron, 1931 with Tetrasticta and repeated this arrangement in his recent paper (Pace 2013a). According to Yamamoto and Maruyama (2013), the synonymization of Tetrasticta by Pace (2010) does not provide sufficient evidence and should not be consider as valid. Currently, no species of this genus has been reported from Mainland China. In 2003, our colleagues Jia-Yao Hu ad Liang Tang surveyed the staphylinid fauna of Nangongshan (Yunnan, Southwest China), and collected a small series of Tetrasticta specimens. A closer examination of this material revealed that the species was undescribed.

Material and methods
All the types are deposited in the Insect Collection of Shanghai Normal University, Shanghai, China (SNUC).
Specimens were killed with ethyl acetate and preserved in 75% ethanol before dissection; photos of habitus were taken with a Canon EOS 7D with an MP-E 65mm macro photo lens.
The following abbreviations are applied in the text: BL -body length, from the anterior margin of the head to the posterior margin of the abdominal tergite VIII; FBL -forebody length, from the clypeal anterior margin to the posterior margin of elytra; HD -head length, from the clypeal anterior margin to the occipital constriction; PL -length of the pronotum along the midline; HW -width of the head across the eyes; PW -maximum width of the pronotum. Description. Body (Fig. 1A) shining. Coloration: head black; antennae and pronotum reddish brown; elytra reddish brown with anterior margin reddish yellow; legs reddish yellow; abdomen with tergites II-IV reddish yellow, tergites VI-VII black.
Head (Figs 1B, C) almost 1.05 times as wide as long; slightly narrower than pronotum; surface sparsely covered with yellow setae; eyes large. Antennae (Figs 1A, D) with segment I long, as long as combined length of segments II-III; segments II and III about one-half of segment I; segment IV extremely short, much wider than long; segments IV-V almost as wide as long; segments VI-X wider than long. Mandibles long, slender. Mentum distinctly transverse, about 3.62 times as wide as long; shaped as in Fig. 1E. Pronotum wider than long, about 1.38 times as wide as long; surface moderately covered with yellow setae; disc with three shallow depressions; shaped as in Fig. 1A. Elytra wider than long; surface moderately covered with yellow setae. Abdomen flattened, with subparallel lateral margins, widest at segments IV-V; tergite VIII with six pairs of macrosetae; sternite VIII ( Fig. 1G) generalized in shape, posterior margin convex in the middle, with eight pairs of macrosetae.
Distribution Remarks. Tetrasticta bobbii is most similar to T. gnatha in overall body shape, relatively long mandibles, but can be readily distinguished form it by the distinctly long antennal segments II-III, the different shape of abdominal tergite VIII and the form of aedeagal median lobe.
Etymology. Named after the Pomeranian dog of senior author.