Stenus biwenxuani, Tang, Liang & Li, Li-Zhen, 2013

Tang, Liang & Li, Li-Zhen, 2013, Discovery of Steninae from Ningxia, Northwest China (Coleoptera, Staphylinidae), ZooKeys 272, pp. 1-20 : 5-7

Stenus biwenxuani sp. n. Figs 1, 226-30

Type material.

Holotype. China: Ningxia: ♂, glued on a card with labels as follows: "Jinyuan County, Erlonghe Linchang, 2100 m, 9.VII.2008, Wen-Xuan Bi leg." "Holotype / Stenus biwenxuani / Tang & Li" [red handwritten label] (SHNU).

Diagnosis.

The new species belongs to the Stenus comma group, and is similar to Stenus atrovestis Puthz, 2008 ( Puthz 2008b). However it can be easily distinguished from the latter by the reddish brown legs, longer elytra and simple metatibiae ( Stenus atrovestis with black legs, shorter elytra and flattened metatibiae).

Description.

Body blackish with a faint plumbeous luster, antennae dark brown with club darker, maxillary palpi yellowish with last and apical half of penultimate segments brownish, legs reddish brown except knee darker with a faint plumbeous luster.

BL: 5.4 mm; FL: 2.7 mm.

HW: 1.00 mm, PL: 0.85 mm, PW: 0.80 mm, EL: 1.15 mm, EW: 1.11 mm, SL: 0.93 mm.

Head 0.90 times as wide as elytra; interocular area with deep longitudinal furrows, median portion moderately convex, not reaching the level of inner eye margins; punctures round, extremely dense, and of similar size; diameter of punctures about as wide as apical cross section of antennal segment III; interstices much narrower than half the diameter of punctures except those along the midline of the convex median portion, which may be a little broader than half the diameter of punctures. Antennae, when reflexed, extending a little beyond middle of pronotum; relative length of antennal segments from base to apex as 12: 10: 17.5: 10: 9: 6.5: 7: 5: 6: 6: 10. Paraglossa oval.

Pronotum 1.06 times as long as wide; disc with shallow and broad median longitudinal furrow fused with pairs of shallow impressions in anterior half, in the middle, and in posterior half; punctures round and very dense, slightly confluent, a little larger than those of head; interstices partially reticulated, of variable width, as wide as half the diameter of punctures or narrower.

Elytra 1.04 times as long as wide; disc slightly uneven with indistinct longitudinal humeral impression, indistinct postero-lateral impression, and indistinct sutural impression; punctures mostly confluent, a little larger than those of pronotum with rugose interstices.

Hind tarsi 0.76 times as long as hind tibiae, tarsomeres IV simple.

Abdomen semi-cylindrical with broad, raised and densely punctate paratergites of segments III–VI, width of paratergites of segment III slightly broader than apical width of metatibiae, punctures slightly larger than those on median portion of tergites; posterior margin of tergite VII with palisade fringe; punctures on abdominal tergites III–VIII round to elliptic, very dense, gradually becoming smaller posteriad; interstices mostly as wide as half the diameter of punctures at most, with relatively faint reticulation on all abdominal tergites.

Male. Mesotibiae and metatibiae each with a subapical tooth on inner side; sternite VI impressed postero-medially with a shallow emargination along the posterior margin of the impression; sternite VII impressed medially, posterior margin of this impression emarginate; sternite VIII (Fig. 26) with emargination at middle of posterior margin; sternite IX (Fig. 27) with apico-lateral projections long and stout, posterior margin serrate; tergite X (Fig. 28) with posterior margin slightly emarginated. Aedeagus (Figs 29, 30) slender, median lobe with a very long and pointed apex; internal plate strongly sclerotized (Fig. 31), parameres extending beneath apex of median lobe, widened and folded in apical third, each with 18 setae on inner side.

Female. unknown.

Distribution.

China (Ningxia).

Etymology.

This species is named in honor of Mr. Wen-Xuan Bi, the collector of the new species.