Stenus shenshanjiai Tang & Puthz

Liang, Tang, Zhao, Yun-Long & Puthz, Volker, 2008, Six new Stenus species of the cirrus group (Coleoptera, Staphylinidae) from China with a key to species of the group, Zootaxa 1745, pp. 1-18 : 8-10

Stenus shenshanjiai Tang & Puthz , sp. nov.

( Figs. 4 , 20–24 )

Type material. Holotype: CHINA: Zhejiang Prov.: ɗ, Wuyi County, Mt. Niutoushan, alt. 400–600 m, 3.VIII.2006, LI Jin-Wen & SHEN Shan-Jia leg.( SHNU). Paratypes: CHINA: Zhejiang Prov.: 3ɗɗ, 2ΨΨ, same data as for the holotype (2ɗɗ, Ψ in SHNU, ɗ, Ψ in cPut).

Description. BL: 2.3–2.8 mm; FL: 1.3 mm.

Proportional measurements of holotype: HW: 39, PW: 29.5, PL: 29, EW: 32, EL: 29.5, SL: 21.

Apterous, black with some brownish tint, slightly glossy; forebody coarsely and very densely punctate and reticulate, abdomen coarsely and moderately sparsely (anteriorly) to finely and very sparsely (posteriorly) punctate; pubescence long, especially erect on abdomen. Antennae yellowish, club infuscate. Maxillary palpi yellowish red. Legs yellowish brown. Clypeus black, labrum dark brown, moderately densely pubescent.

Head 1.22 times as wide as elytra; clypeofrontal area densely punctate and pubescent; basiantennal tubercles small; interocular area with deep longitudinal furrows, median portion convex, extending to the level of inner eye margins; punctures round to elliptic, larger and sparser on median area than those near inner margins of eyes, diameter of large punctures about as wide as basal cross section of 2nd antennal segment, interstices between punctures with dense mesh sculpture, distinctly smaller than half diameter of punctures, larger along midline. Antennae when reflexed extending a little short of posterior margin of pronotum; 3rd to7th segments much narrower than 2nd; 8th to 11th gradually broadened, forming loose club; relative length of segments from base to apex as 6.5: 4.5: 9.5: 5.0: 4.5: 3.0: 2.5: 2.0: 3.0: 3.5: 5.0. Paraglossae oval.

Pronotum slightly wider than long, 0.92 times as wide as elytra, widest near middle and constricted at base; disk uneven, with broad and shallow median longitudinal furrow which is about 2/3 the length of pronotum, and two impressions in posterior half; punctures round, some of them confluent, different in size, diameter of large punctures about as wide as medial cross section of 2nd antennal segment, interstices with dense mesh sculpture, smaller than half diameter of punctures.

Elytra 0.92 times as long as wide, distinctly constricted at base, lateral margins gently divergent posteriad; posterior conjoint margins roundly and distinctly emarginate at middle; disk uneven with faint humeral impression, faint sutural impression and moderately distinct postero-lateral impression; punctation coarse and very dense, punctures larger than those on pronotum, insterstices distinctly smaller than half diameter of punctures.

Legs elongate, hind tarsi 0.74 times as long as hind tibiae, 4th tarsomeres strongly bilobed.

Abdomen cylindrical; paratergites very narrow and punctate, present only in 3rd segment, no apical membranous fringe at tergite 7; punctures round to elliptic, gradually becoming smaller posteriad, each puncture with long and suberect seta, interstices smooth, varied from smaller to larger than diameter of punctures.

Male. Seventh sternite flattened at posteromedian part with faint emargination along posterior margin of flat area; 8th sternite ( Fig. 20 ) with shallow emargination at middle of posterior margin; 9th sternite ( Fig. 21 ) with long apicolateral projections, posterior margin serrate and nearly straight. Aedeagus ( Fig. 22 ) with median lobe broadest at about basal 2/5, tapering apicad, apical sclerotized area with round projection at apex, expulsion clasp ( Fig. 23 ) strongly sclerotized; parameres slender, distinctly longer than median lobe, slightly swollen at apex, each with about 8–10 setae on apico-internal margins.

Female. Abdomen broader than that in male; 8th sternite with posterior margin weakly pointed at middle; sclerotized spermatheca as in Fig. 24 .

Remarks. This new species resembles S. nigritus Tang et al., 2005 described from Shaanxi Province, but may be distinguished easily by broader head, much more regular punctation on elytra and different sexual characters.

Distribution. China (Zhejiang Province).

Etymology. This species is named in honor of Mr. SHEN Shan-Jia, who collected some Stenus specimens used in this study and helped us in many other ways.

Figures

FIGURES 1 – 6. Stenus cirrus group, habitus. 1 — S. zhulilongi sp. nov., female; 2 — S. lijinweni sp. nov., male; 3 — S. jiulongshanus sp. nov., male; 4 — S. shenshanjiai sp. nov., male; 5, S. — flammeus sp. nov., male; 6 — S. bostrychus sp. nov., male. Scale bars 1 mm.

FIGURES 20 – 24. Details of Stenus shenshanjiai sp. nov. 20 — male 8 th sternite; 21 — male 9 th sternite; 22 — aedeagus in ventral view; 23 — expulsion clasp of aedeagus; 24 — spermatheca. Scale bars 0.25 mm.