Lathrobium yinziweii Peng and Li

Peng, Zhong, Li, Li-Zhen & Zhao, Mei-Jun, 2013, Eight new apterous Lathrobium species (Coleoptera, Staphylinidae) from Sichuan, Southwest China, ZooKeys 303, pp. 1-21 : 11-14

Lathrobium yinziweii Peng and Li sp. n. Figs 6B, 8, 15

Type material.

(3 ♂♂, 4 ♀♀). Holotype: ♂, labelled 'CHINA: Sichuan Prov., Shimian County, Liziping. Yele, 28°54'N, 102°13'E, 15.vii.2012 alt. 2,600 m, Dai, Peng & Yin leg.' (SNUC). Paratypes: 2 ♂♂, 4 ♀♀, same label data as holotype (SNUC).

Description.

Measurements and ratios: BL 5.50-6.89, FL 2.40-2.82, HL 0.72-0.79, HW 0.75-0.78, PL 0.96-1.07, PW 0.77-0.82, EL 0.51-0.57, AL 1.67-1.72, HL/HW 0.96-1.01, HW/PW 0.95-0.97, HL/PL 0.73-0.76, PL/PW 1.25-1.30, EL/PL 0.52-0.54.

Habitus as in Fig. 6B. Body light brown with paler apex, legs yellowish brown, antennae light brown.

Head subquadrate (HL/HW 0.96-1.01); punctation moderately coarse and sparse, sparser in median dorsal portion; interstices with fine microreticulation; eyes 1/5-1/4 times as long as postocular region in dorsal view.

Pronotum slender; punctation somewhat denser than that of head; impunctate midline broad; interstices without microreticulation.

Elytra 0.52-0.54 times as long as pronotum; punctation fine, shallow, and moderately dense. Hind wings completely reduced. Protarsi with moderately pronounced sexual dimorphism.

Abdomen with fine and dense punctation, that of tergite VII sparser than that of anterior tergites; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII with moderately pronounced sexual dimorphism.

Male. Tergite VIII with nearly truncate posterior margin; sternites III-VI unmodified; sternite VII (Fig. 8D) transverse and with shallow postero-median impression, pubescence very weakly modified, posterior margin concave in the middle; sternite VIII (Fig. 8E) broadly impressed along the middle, this impression with short modified setae, posterior margin shallowly concave in the middle; sternite IX (Fig. 8G) asymmetric; aedeagus as in Figs 8F, 8H; ventral process very long, slender, evenly curved, and apically indistinctly spear-shaped; basal portion of dorsal plate very short; internal sac with membranous structures and usual ring-shaped structure.

Female. Posterior margin of tergite VIII (Fig. 8A) weakly convex; sternite VIII (Fig. 8B) much longer than tergite VIII and rather narrowly produced posteriorly; tergites IX-X (Fig. 8C) long and slender, tergite X (Fig. 8C) 1.4 times as long as antero-median portion of tergite IX (Fig. 8C).

Distribution and biological notes.

This species is currently known only from the type locality. One male was collected by sifting bamboo leaves and humus from the floor of the bamboo forest (Fig. 15). The other specimens were collected by sifting litter of bamboo and rhododendronfrom the floor of a rhododendron forestat an altitude of 2,600 m.

Etymology.

The species is named after Yin Zi-Wei, who collected the type specimens.

Comparative notes.

Lathrobium yinziweii is evidently closely related to Lathrobium diffissum (Assing, in press b) from the Luoji Shan. Both species share an aedeagus of similar morphology (ventral process long, slender, curved, and apically indistinctly spear-shaped; basal portion of dorsal plate very short; internal sac without sclerotized structures), a similar shape of the male sternite VII and sternite VIII (the posterior margin concave in the middle), a male sternite VIII with dense, but not distinctly modified pubescence, and a long and undivided antero-median portion of the female sternite IX. Lathrobium yinziweii is distinguished by the shape of the male sternite VIII (not transverse and with posterior excision), by the morphology of the aedeagus (ventral process evenly curved and slender; dorsal plate longer), by the shape of female sternite VIII, and by the long and slender female tergite IX-X.