Stenus yaoluopingus 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 : 342-344

Stenus yaoluopingus Hu & Tang , sp. n.

( Figs. 1 , 5–10 )

Type Material. Holotype: China: Anhui: ♂, glued on a card with labels as follows: “ China: Anhui Prov., Yue’xi County, Yaoluoping N. R., Duozhijian , 30°58'38''N, 116°06'59''E, 1650m, 19.VI.2013, Dai & Peng leg.” “ Holotype / Stenus yaoluopingus / Hu & Tang” [red handwritten label] ( SHNU) . Paratypes: 9♂♂ 9♀♀, same data as for the holotype. ( SHNU, cPut)

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

BL: 3.6–4.3 mm, FL: 1.8–2.1 mm.

HW: 0.79–0.94 mm, PL: 0.62–0.69 mm, PW: 0.56–0.63 mm, EL: 0.64–0.73 mm, EW: 0.67–0.76 mm, SL: 0.47–0.53 mm.

Head 1.17–1.26 times as wide as elytra; interocular area with deep longitudinal

furrows, median portion convex, extending beneath the level of inner eye margins; punctures round and mostly well delimited, those near antennal tubercles more or less 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, much narrower than half the diameter of punctures except a few near inner margins of eyes and along the midline of the convex median portion, which may be two to three wider than diameter of punctures. Paraglossae oval.

Pronotum 1.07–1.15 times as long as wide; disk relatively uneven, with short and shallow median longitudinal furrow, distinct transverse impression along anterior margin and two indistinct transverse impressions in the middle; punctures more or less confluent, different in size, larger punctures slightly wider than apical cross section of antennal segment II; interstices smooth, much narrower than half the diameter of punctures to slightly wider than diameter of punctures.

Elytra 0.91–1.02 times as long as wide; lateral margins slightly concaved in the middle; disk uneven with distinct longitudinal humeral impression, distinct sutural impression and distinct postero-lateral impression, suture convex; punctation and interstices similar to those of pronotum except punctures slightly larger in average.

Legs with tarsomeres IV deeply bilobed.

Abdomen cylindrical; segments III–VI with tergites and sternites entirely fused, paratergites absent though traces of degenerated paratergites can be recognized in basal half of these segments; posterior margin of tergite VII with indistinct apical membranous fringe; punctation elliptic to round, gradually becoming smaller posteriad; interstices narrower than half the diameter of punctures to narrower than diameter of punctures, those of tergites III and IV smooth, those of tergites V and VI partially and indistinctly microsculptured, those of rest tergites microsculptrued.

Male. Sternite VII with posteromedian portion flattened; sternite VIII ( Fig. 5 ) with shallow emargination at middle of posterior margin; sternite IX ( Fig. 6 ) with very long apicolateral projections, posterior margin serrate. Aedeagus ( Figs. 7, 8 ) with median lobe slender, apical sclerotized area subtriangular and roundly projected at apex; expulsion clasps large; parameres much longer than median lobe, slightly swollen at apical third, each with 16–19 setae on apico-internal margins.

Female. Sternite VIII ( Fig. 9 ) prominent at middle of posterior margin; spermatheca ( Fig. 10 ) strongly sclerotized with coiled spermathecal duct, large apical chamber and large capsule.

Distribution. China (Anhui).

Remarks. The new species is very similar to S. paradecens Tang & Li, 2005 from Anhui province, and can be distinguished from the latter by more distinct pronotal median furrow and more confluent pronotal punctation.

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

Figures

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

FIGURES 5–10. Stenus yaoluopingus. 5 male sternite VIII 6 male sternite IX 7, 8 aedeagus 9 female sternite VIII 10 valvifers and spermatheca. Scale bars: 0.25 mm.