Notes on the genus Episcaphium Lewis (Coleoptera, Staphylinidae, Scaphidiinae) with description of a new species from China

Abstract A new Episcaphium species collected from Yunnan Province of China is described as Episcaphium zhuxiaoyui sp. n., and its diagnostic characters are illustrated. A new province record of Episcaphium haematoides is reported. A key to the Episcaphium species recorded from China is provided.

Recently, we examined some specimens of the genus, among them a new species and a new province record.

Material and methods
Specimens were mainly collected by hand from decayed wood and fungi in broadleaved forests and killed with ethyl acetate. For examination of the male genitalia, the last two abdominal segments were detached from the body after softening the specimens in hot water. The aedeagi were mounted in Euparal (Chroma Gesellschaft Schmidt, Koengen, Germany) on plastic slides. Photos of the aedeagi were taken with a Canon G9 camera attached to an Olympus SZX 16 stereoscope; habitus photos were taken with a Canon macro photo lens MP-E 65 mm attached to a Canon EOS7D camera and stacked with Zerene Stacker (http://www.zerenesystems.com/cms/stacker).
The type specimens treated in this study are deposited in the following public and private collections: Frons at narrowest point 0.42-0.44 mm wide. Head coarsely and very densely punctate, punctation coarse on vertex and fine near eyes. Intervals between punctures distinctly smaller than diameter of punctures. Between eyes with a pair of impunctate patches. Labium smooth. Gular striae impressed, groove-like basally.
Elytra with shallow apical impression and indistinct humeral protuberance; disc with four discal puncture rows consisting of rather coarse punctures anteriorly gradually becoming finer posteriad. All rows start at about basal 2/11 of elytron and end blurrily where puncture rows mix with apical disc punctures. Punctation fine between  discal series of punctures and coarse in apical impressions. Mesoventral process with raised, ridge-like edges, and impressed in middle.
Punctation of abdominal sternites very fine and very sparse. Micropunctures absent. Male sexual characters. Segments 1 to 3 of protarsi slightly widened with dense setae on ventral side. Aedeagus (Figs 5, 6) with median lobe with apical portion inflexed in lateral view. Basal process small, slightly prominent. Parameres slightly sinuate in lateral view. Internal sac (Fig. 7) with a pair of comma-like sclerotized rods.
Remarks. This new species is similar to the variety of E. semirufum Lewis, 1893 with dark head described from Japan (Figs 3, 4, 8-10), but it may be distinguished from the latter by the different coloration of the ventral side, a pronotum with the antebasal puncture row usually interrupted at middle, and the formation of the discal puncture rows on the elytra: the two outer rows are distinctly separated from the basal puncture row, while in E. semirufum, they fuse with the basal puncture row. The new species is distinguished from all the other species by its coloration.
Etymology. This species is named in honor of Mr. Xiao-Yu Zhu who collected some specimens of the new species.
Biological notes. This species was found gathering on an unknown fungus on a huge rotten log across stream, and was observed to become active when night fell (Figs 11,12). Distribution. This species was previously known from Yunnan and Sichuan. The above male represents the first record from Gansu.