Stenus lizipingus Hu & Tang, 2018

Hu, Cheng-Zhi & Tang, Liang, 2018, Notes on the Stenus indubius group with descriptions of four new species from China (Coleoptera, Staphylinidae), Zootaxa 4471 (2), pp. 341-350 : 344-345

Stenus lizipingus Hu & Tang , sp. n.

( Fig. 2 , 11–16 )

Type Material. Holotype: China: Sichuan: ♂, glued on a card with labels as follows: “ China: Sichuan Prov., Shimian County, Liziping, Yele Dam , 28°55'N, 102°13'E, 2600m, 15.VII.2012, Peng, Dai & Yin leg.” “ Holotype / Stenus lizipingus / Hu & Tang” [red handwritten label] ( SHNU) . Paratypes: 2♀♀, same data as for the holotype. ( SHNU, cPut) ; 1♂ 2♀♀, Mianning County, Yele Daba , 28°55'22''N, 102°13'32''E, 2500m, 25.VII.2015, Jiang, Peng, Tu & Zhou leg. ( SHNU)

Description. Brachypterous. Body dark brown with head slightly darker. Antennae, maxillary palpi and legs reddish brown.

BL: 4.1–4.5 mm, FL: 2.0– 2.3 mm.

HW: 0.85–0.94 mm, PL: 0.67–0.70 mm, PW: 0.61–0.68 mm, EL: 0.68–0.73 mm, EW: 0.73–0.86 mm, SL: 0.51–0.54 mm.

Head 1.05–1.25 times as wide as elytra; interocular area with deep longitudinal furrows, median portion convex, extending to the level of inner eye margins; punctures round, slightly confluent, most punctures similar in size except a few near inner margins of eyes smaller, diameter of larger punctures slightly narrower than apical cross section of antennal segment II; interstices smooth, rarely those of posterior potion indistinctly reticulated, much smaller than half the diameter of punctures except those of median potion, which could be as wide as half the diameter of punctures. Paraglossa oval.

Pronotum 1.01–1.10 times as long as wide; disk distinctly uneven, with deep median longitudinal furrow; punctation very confluent with punctures smaller than those of head; interstices partially with indistinct microsculpture, ridge-like, revolving around median longitudinal furrow, narrower than to distinctly wider than diameter of punctures.

Elytra 0.85–0.96 times as long as wide; disk uneven with deep longitudinal humeral impression, deep sutural impression and distinct posterolateral impression, suture convex; punctation and interstices similar to those of pronotum.

Legs with tarsomeres IV deeply bilobed.

Abdomen cylindrical; segments III–VI without paratergites, tergites and sternites distinctly separated by lateral sutures; posterior margin of tergite VII with indistinct apical membranous fringe; punctation of abdominal tergites elliptic to round, gradually becoming smaller posteriad, punctures of tergite III slightly larger than those of head in average; tergite III with microsculptures indistinct, which becoming graudually distinct posteriad, interstices of tergite III–VI narrower than half the diameter of punctures to narrower than diameter of punctures.

Male. Sternite VIII ( Fig. 11 ) with emargination in the middle of posterior margin; sternite IX ( Fig. 12 ) with very long apicolateral projections, posterior margin serrate. Aedeagus ( Figs. 13, 14 ) with median lobe stout, apical sclerotized area short with anterior margin round; expulsion clasps large; parameres distinctly longer than median lobe, swollen at apical fourth, each with 20–25 setae on apico-internal margins.

Female. Sternite VIII ( Fig. 15 ) slightly prominent at middle of posterior margin; spermatheca ( Fig. 16 )sclerotized, spermathecal duct with two bents, first bent coiled, apical chamber very large and capsule large.

Distribution. China (Sichuan).

Remarks. The new species is very similar to S. zhuxiaoyui Tang & Zhao, 2008 , S. pectorifossatus Tang & Zhao, 2008 and S. erlangshanus Tang & Zhao, 2008 from Sichuan, and can be distinguished from S. zhuxiaoyui and S. erlangshanus by more confluent pronotal punctation and denser abdominal punctation, from S. zhuxiaoyui by larger body size (FL: 1.5–2.0 mm in S. zhuxiaoyui ) and deeper elytra impressions, from S. erlangshanus by lacking distinct subbasal and subapical pronotal impressions and abdominal tergites mostly with microsculptures, and from S. pectorifossatus by darker elytral coloration and sparser abdominal punctation.

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

Figures

FIGURES 1, 2. Habitus. 1 Stenus yaoluopingus 2 S. lizipingus. Scale bars: 1mm.

FIGURES 11–16. Stenus lizipingus. 11 male sternite VIII 12 male sternite IX 13, 14 aedeagus 15 female sternite VIII 16 valvifers and spermatheca. Scale bars: 0.25mm.