Stenus erlangshanus Tang

Tang, Liang & Yun-Long, Zhao, 2008, Three new Stenus species of the indubius group (Coleoptera, Staphylinidae) from China, Zootaxa 1741, pp. 51-58 : 56-57

Stenus erlangshanus Tang , sp. nov.

( Figs. 3 , 14–18 )

Type material. Holotype: CHINA: Sichuan Prov.: ɗ, Tianquan County, Labahe, alt. 2400–2600m, 31.VII.2006, HU Jia-Yao & TANG Liang leg. ( SHNU) Paratypes: CHINA: Sichuan Prov.: 2ΨΨ, same data as for the holotype (Ψ in SHNU, Ψ in cPut); Ψ, Tianquan County, Erlangshan, alt. 1600–2000m, 29.VII.2006, HU Jia-Yao & TANG Liang leg. ( SHNU)

Description. BL: 3.8–4.2 mm; FL: 1.9–2.3 mm.

Proportional measurements of holotype: HW: 48.5, PL: 39.5, PW: 36.0, EL: 39.0, EW: 41.5, SL: 27.0; relative length of segments from base to apex as 7.0: 5.5: 10.5: 6.5: 6.5: 4.5: 4.0: 3.5: 4.0: 4.0: 6.5; hind tarsi 0.75 times as long as hind tibiae.

Brachypterous, blackish brown, moderately glossy, head and abdomen coarsely and very densely, pronotum and elytra coarsely and very rugosely punctate; pubescence short, recumbent. Antennae light brown, club somewhat infuscate. Maxillary palpi and legs light brown. Clypeus blackish, labrum dark brown, densely pubescent.

In most respects S. erlangshanus is very similar to S. zhuxiaoyui , but different in the following characters: diameter of large puncture on head about as wide as apical cross section of 2nd antennal segment; pronotum with median longitudinal furrow and impressions very deep, punctation very rugose and confluent; elytra with suture relatively less strongly convex and punctation very rugose and confluent.

Male. Seventh sternite ( Fig. 14 ) with slight emargination at middle of posterior margin; 8th sternite ( Fig. 14 ) with triangular emargination at middle of posterior margin; 9th sternite ( Fig. 15 ) with very long apicolateral projections, posterior margin serrate. Aedeagus ( Fig. 16 ) with median lobe gradually narrowed apicad into an obtuse membranous apex; expulsion hooks ( Fig. 17 ) large, internal sac as in Fig. 16 ; parameres extending distinctly beyond apex of median lobe, almost straight, swollen at the beginning of their apical 2/5, which are distinctly narrowed toward apex, with about 23 subapical setae.

Female. Abdomen broader than that in male; 8th sternite with posterior margin slightly pointed at middle; sclerotized spermatheca as in Fig. 18 .

Remarks. See remarks for S. zhuxiaoyui .

Distribution. China (Sichuan Province).

Etymology. The specific name is derived from “Er’langshan”, the type locality of this species.

Figures

FIGURES 1 – 3. Adult habitus. 1 — Stenus zhuxiaoyui sp. nov.; 2 — S. pectorifossatus sp. nov.; 3 — S. erlangshanus sp. nov. Scale = 1 mm.

FIGURES 14 – 18. Details of Stenus elangshanus sp. nov. 14 — male 7 – 8 th sternites; 15 — male 9 th sternite; 16 — aedeagus in ventral view; 17 — expulsion hooks of aedeagus; 18 — spermatheca. Scale = 0.25 mm.