Stenus yuyimingi Liu, Tang & Luo

Liu, Sheng-Nan, Tang, Liang & Luo, Rong-Ting, 2017, Notes on the Stenuscirrus group of Zhejiang, East China, with descriptions of two new species (Coleoptera, Staphylinidae), ZooKeys 684, pp. 75-84 : 77-80

Stenus yuyimingi Liu, Tang & Luo sp. n. Figs 3, 4, 14-20

Type material.

CHINA: Zhejiang: Holotype: ♂, glued on a card with labels as follows: "China: S. Zhejiang, Lishui City, Longquan Fengyangshan N.R., forest nr. Xiabian Vil., 27°55 ’58’’ N, 119°10 ’57’’ E, mixed leaf litter, sifted, 690-780 m, 9.X.2013, Z. Peng, Y.-M. Yu, Z.-W. Yin leg". "Holotype / Stenus yuyimingi / Liu & Tang" [red handwritten label] (SHNU). Paratypes: 1♂, same data as for the holotype, but Mihougu, 27°55 ’0.18’’ N, 119°11 ’52.91’’ E, near stream, 1116 m, 03.V.2016, Jiang, Liu & Zhou leg (SHNU); 1♂, same data as for the holotype, but Datianping, 27°54'33 ‘’-55’18’’ N, 119°10 ’20’’-17’’ E, mixed litter, moss, sifted, 1170-1300 m. 7.X.2013, Feng, Peng, Yu, Yin leg. (cPut); 1♂, same data as for the holotype, but Jitou Vil., 27°55 ’58’’ N, 119°12 ’44’’ E, fern, silvergrass, fir, sifted, ca, 1050 m, 9.X.2013, Z Peng, Y.-M. Yu, Z.-W. Yin leg. (SHNU); 1♂1♀, same data as for the holotype, but Da-Tian-Ping 27°54 ’36‘’ N, 119°10 ’20’’ E, bush leaf, moss, ferns, sifted & beating, 1320 m. 27.IV.2014, Peng, Song, Yan, Yin & Yu leg. (SHNU); 1♀, same data as for the holotype (SHNU); 1♀, same data as for the holotype, but Luao Vil., 27°55 ’00’’ N, 119°11 ’53’’ E, moss, fern, bamboo, bush, sifted, 1130 m, 4.X.2013, Z Peng, Y.-M. Yu, Z.-W. Yin leg. (SHNU).

Description.

Brachypterous. Head black, pronotum and elytra brown, each elytron with median portion inconspicuously lighter, abdomen dark brown. Antennae, maxillary palpi and legs yellowish brown except antennal club infuscate. Labrum reddish brown.

BL: 3.6-4.4 mm, FL: 1.8-2.1 mm. HW: 0.77-0.86 mm, PL: 0.61-0.69 mm, PW: 0.56-0.66 mm, EL: 0.70-0.78 mm, EW: 0.70-0.85 mm, SL: 0.52-0.59 mm.

Head 1.02-1.09 times as wide as elytra; interocular area with two deep longitudinal furrows, median portion convex, extending to the level of inner eye margins; punctures round, distinctly larger and sparser in median portion than those near inner margins of eyes, diameter of large punctures slightly wider than apical cross section of antennal segment II; interstices smooth, narrower than half the diameter of punctures except those along the midline of the median portion, which may be as wide as the diameter of punctures. Paraglossae oval.

Pronotum 0.98-1.10 times as long as wide; disk relatively even with median longitudinal furrow very short and indistinct; punctures mostly round and slightly confluent, similar size to those of head; interstices smooth, mostly narrower than diameter of punctures except in median area, which may be triple as wide as diameter of punctures.

Elytra 0.93-1.00 times as long as wide; disk relatively even; punctures slightly and longitudinally confluent, of similar size to those of pronotum; interstices smooth, distinctly narrower than diameter of punctures.

Legs with tarsomeres IV strongly bilobed.

Abdomen cylindrical; paratergites very narrow and almost impunctate, present only in segment III, tergites and sternites totally fused in segments IV–VI, posterior margin of tergite VII with indistinct palisade fringe; punctures round, gradually becoming smaller and sparser posteriad; interstices smooth, mostly wider than diameter of punctures except those on basal impressions of tergites III–V, which may be distinctly narrower than half the diameter of punctures.

Male. Sternite VII (Fig. 14) with inconspicuous emargination at middle of posterior margin; sternite VIII (Fig. 15) with shallow emargination at middle of posterior margin; sternite IX (Fig. 16) with short apicolateral projections, posterior margin serrate. Aedeagus (Figs 17-18) apical sclerotized area triangular with a sharp projection at apex; median longitudinal bands each with ventral band very long, straight, narrowed apically; lateral longitudinal bands short; expulsion clasps each with anterior plate distinctly separated from the posterior plate, rounded apically; copulatory tube very long, rather slender, with basal chamber submembranous and main tube, the main tube gradually shrink, pointed apicaly; parameres as long as median lobe, each with about 19-22 setae on apico-internal margins.

Female. Sternite VIII (Fig. 19) entire; spermatheca (Fig. 20) strongly sclerotized, swollen in the middle of spermathecal duct.

Distribution.

China (Zhejiang).

Remarks.

The new species can be easily distinguished from the Chinese members of the group by the coloration and sexual characters.

Etymology.

This species is named in honor of Mr. Yi-Ming Yu who collected some specimens of the new species.