New species and records of Lobrathium Mulsant & Rey (Coleoptera, Staphylinidae, Paederinae) from China

Abstract Seven new species of the genus Lobrathium Mulsant & Rey from China are described and illustrated: Lobrathium anatinum Li & Li, sp. n. (Guangxi), Lobrathium diaoluoense Li & Li, sp. n. (Hainan), Lobrathium dufui Li & Li, sp. n. (Hubei), Lobrathium lirunyui Li & Li, sp. n. (Guizhou), Lobrathium pengi Li & Li, sp. n. (Guangxi), Lobrathium quyuani Li & Li, sp. n. (Hubei) and Lobrathium uncinatum Li & Li, sp. n. (Qinghai). A recent key to the species of mainland China is modified to accommodate the new species. New locality data are provided for eleven species.


Introduction
According to a recent revision (Assing 2012), the genus Lobrathium Mulsant & Rey, 1878 is represented in China by 43 species (24 species from mainland China and 20 from Taiwan, with Lobrathium hongkongense distributed both in mainland China and Taiwan). Later, Li et al. (2013)    Description. Body length 7.28-7.89 mm, length of fore body 3.89-4.0 mm. Habitus as in Fig. 2A. Coloration: body black with distinct bluish hue, middle of elytra with yellowish spot not reaching lateral and posterior margins; legs blackish with paler tarsi, antennae dark brownish to blackish.
Head weakly transverse (HW/HL = 1.10-1.11), widest across eyes; posterior angles broadly rounded; punctation dense and moderately coarse, sparser in median dorsal portion; interstices without microsculpture. Eyes large, more than half as long as distance from posterior margin of eye to neck in dorsal view. Antenna long and slender, 1.96-2.22 mm long.
Pronotum 1.24-1.30 times as long as broad, as wide as head (PW/HW = 1.0), lateral margins convex in dorsal view, punctation similar to that of head, but with impunctate midline, interstices glossy.
Abdomen broader than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe.
Male. Sternite VII (Fig. 2D) strongly transverse and with distinct median impression, this impression without pubescence, posterior margin broadly concave; sternite VIII ( Fig. 2E) weakly transverse, with long and pronounced postero-median impression, this impression with numerous modified, stout and short black setae, posterior excision moderately broad and moderately deep, on either side of this excision with long dark setae; aedeagus (Figs 2B, C) 1.70-1.72 mm long, ventral process long, flattened, and apically convex in ventral view.
Female. Unknown Etymology. The specific epithet (Latin, adjective: of a duck) refers to the shape of the ventral process of the aedeagus, which somewhat resembles the mouth of a duckbill.
Comparative notes. This species is close to L. ablectum Assing (2012) in sharing a similar shape and chaetotaxy of the sternites VII and VIII. The new species differs from L. ablectum by larger body size, and by the longer, apically not bifid ventral process of the aedeagus.
Habitat and distribution. The present species was sifted from wet moss near a cold stream (Fig. 20A) in the Angjiangping National Reserve, Guangxi (Fig. 19), in July.     Head as long as broad or weakly oblong (HL/HW = 1.0-1.09); posterior angles marked; punctation coarse and dense, sparser in median dorsal portion, interstices without microsculpture. Eyes large, more than half as long as distance from posterior margin of eye to neck. Antenna slender, 1.54-1.78 mm long.
Abdomen distinctly narrower than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII weakly concave, without appreciable sexual dimorphism.
Male. Sternite VII (Fig. 7D) with deep and broad median impression without pubescence, posterior margin broadly and rather strongly concave; sternite VIII oblong, with deep and large U-shaped posterior excision (Fig. 7F), without modified setae, on either side of posterior excision with long dark setae; aedeagus (Figs 7B, C) with ventral process of very distinctive morphology, furcate apically, and this bifurcation forming an angle of less than 30 degrees in lateral view.
Etymology. The specific epithet (adjective) is derived from the Diaoluo Shan where the type locality is situated.
Comparative notes. This species is similar to L. bipeniculatum Assing (2010) and L. pengi Li & Li sp. n. (described below) in sharing similar shapes of the male sternites VII and VIII, and of the aedeagus. It can be separated from L. bipeniculatum by the broader median impression of the male sternite VII (Fig. 7D), and by the absence of clusters of long dark setae at the margins of the posterior excision of the male sternite VIII (Fig. 7F). In L. pengi, the ventral process of the aedeagus is of different shape, with the apical bifurcation forming an angle of more than 30 degrees in lateral view.
Habitat and distribution. The present species was sifted from wet moss on stones alongside a reservoir (red circle in Fig. 20B) in the Diaoluo Shan, Hainan (Fig. 19), in April. Description. Body length 5.84-6.89 mm, length of fore body 3.34-3.61 mm. Habitus as in Fig. 8A. Coloration: body black, posterior portion of elytra with oblong yellowish spot of at least 2/5 the length of elytra and reaching posterior margins and lateral margins; legs blackish with slightly paler tibiae and tarsi; antennae brown.
Head weakly transverse (HW/HL = 1.02-1.09), widest at eyes, weakly tapering behind eyes; posterior angles rounded, not marked; punctation coarse and moderately dense, sparser in median dorsal portion and on frons; interstices without microsculpture. Eyes large, more than half the length of postocular region from posterior margin of eyes to neck in dorsal view. Antenna slender, 1.72-2.18 mm long.
Male. sternite VII (Fig. 8D) transverse and posteriorly with pronounced impression of triangular shape, this impression impunctate in the middle and laterally with a few modified, stout and short black setae, posterior margin broadly and weakly concave; sternite VIII ( Fig. 8E) weakly transverse, with deep and broad, U-shaped posterior excision, median impression furnished with numerous modified, stout, short and black setae; aedeagus (Figs 8B, C) with ventral process of very distinctive morphology, apically with fissure and bifid.
Etymology. The species is named after the famous late poet Fu Du, who was born in Hubei.
Comparative notes. This species is similar to L. uncinatum Li & Li sp. n. (described below) in external characters, and to L. hebeatum Zheng (1988) in sexual characters. It differs from L. uncinatum by the shape of the aedeagus and by the absence of modified setae on the male sternite VI, and from L. hebeatum by the shape of the apex of the ventral process of the aedeagus.
Habitat and distribution. The type specimens were sifted from wet moss near a stream (Fig. 20C) in Hubei (Fig. 19).  Description. Large species, body length 9.40 mm, length of fore body 4.20 mm. Habitus as in Fig. 11A. Body reddish brown, legs reddish with pale-reddish tarsi, antennae reddish to brown.

Lobrathium hebeatum
Head longer than wide (HL/HW = 1.06), widest posteriorly; posterior angles weakly marked; punctation of dorsal surface fine and very dense; interstices without microsculpture. Eyes small, approximately one third the length of distance from posterior margin of eye to neck in dorsal view. Antenna long and slender, 2.50 mm long.  Pronotum slender (PL/PW = 1.28, PW/HW = 0.90), lateral margins almost straight and subparallel in dorsal view; punctation similar to that of head, but with impunctate midline.
Abdomen distinctly narrower than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe.
Male. Sternite VII (Fig. 11D) strongly transverse, and with shallow median impression posteriorly, without modified setae, posterior margin broadly and weakly concave; sternite VIII ( Fig. 11E) weakly transverse, with long and extensive posteromedian impression, this impression with numerous modified, stout and short black setae, posterior excision rather broad and U-shaped, on either side of this excision with long dark submarginal setae; aedeagus (Figs 11B, C) 1.56 mm long, with asymmetric ventral process of distinctive shape.

Female. Unknown
Etymology. The species is named after Runyu Li, collector of the holotype. Comparative notes. This species is readily distinguished from all its congeners by the following character combination: elytra without spot, whole body of brownish coloration; punctation of head fine and dense, eyes very small, one third as long as distance from posterior margin of eye to neck, male sexual characters highly distinctive.

Lobrathium pengi
Head weakly transverse (HW/HL = 1.02-1.03); posterior angles not marked; punctation coarse and dense, sparser in median dorsal portion, interstices without microsculpture. Eyes large, more than half as long as the distance from posterior margin of eye to neck. Antenna slender, 1.68-1.82 mm long.
Abdomen distinctly narrower than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe; tergite VIII ( Fig. 12F) without appreciable sexual dimorphism, with weakly convex posterior margin.

Female. Sternite VIII as in
Etymology. The species is named after Zhong Peng, collector of the type specimens. Comparative notes. This species is similar to L. diaoluoense, from which it is separated by the broader and apically more abruptly narrowed ventral process of the aedeagus, with the apical bifurcation forming an angle of more than 30 degrees in lateral view.
Head as wide as long (HW/HL = 0.96-1.03), widest at eyes; posterior angles broadly rounded; punctation dense and moderately coarse, sparser in median dorsal portion; interstices without microsculpture. Eyes large, more than half as long as the distance from posterior margin of eye to neck in dorsal view. Antenna slender, 1.72-1.95 mm long.
Abdomen narrower than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII strongly convex in the middle.
Male. Sternite VII (Fig. 13D) strongly transverse, posteriorly with pronounced median impression, this impression of somewhat triangular shape, without punctation and pubescence, posterior margin broadly and very weakly concave; sternite VIII ( Fig. 3E) weakly transverse, postero-median impression with modified, stout and short black setae, posterior excision deep and moderately broad, on either side of this excision with long dark submarginal setae; aedeagus (Figs 13B, C) 1.36 mm long, with weakly asymmetric and apically acute ventral process.
Female. Unknown Etymology. The specific epithet refers to the famous late poet Yuan Qu, who was born in Yichang (Hubei), which is near the type locality. Comparative notes. This species is similar to L. configens Assing (2012) and L. spathulatum Assing (2012) in external characters. It is distinguished from both by the broader ventral process in ventral view.

Lobrathium spathulatum
Head transverse (HW/HL = 1.14); posterior angles not marked; punctation coarse and dense, sparser in median dorsal portion, interstices without microsculpture. Eyes large, more than half as long as distance from posterior margin of eye to neck. Antenna slender, 1.92 mm long. Pronotum moderately oblong, as wide as head (PL/PW = 1.18, PW/HW = 1.0); lateral margins subparallel in dorsal view; punctation dense and coarse, similar to that of head, but with impunctate midline; interstices without microsculpture and glossy.
Abdomen narrower than elytra; punctation fine and dense; posterior margin of tergite VII with palisade fringe.