Stenus wutongshanus Tang, Xu & Xia, 2019

Tang, Liang, Xu, Wang & Xia, Mei-Hua, 2019, A study on the genus Stenus Latreille from Shenzhen City of Guangdong, South China (Coleoptera, Staphylinidae), Zootaxa 4615 (2), pp. 365-374 : 369-372

12. Stenus wutongshanus Tang, Xu & Xia , new species

( Figs. 5–14 )

Type material. Holotype. China: Guangdong: Shenzhen: ♂, glued on a card with labels as follows: “China: Guangdong Province, Shenzhen City , Mt. Wutong , Taishanjian , mixed leaf litter, sifted, 22°35’50.94’’N, 114°10’47.96’’E, alt. 900m, 26.III.2019, Tang, Shuai, Zhao, Zhou & Xia leg.” “Holotype / Stenus wutongshanus / Tang, Xu & Xia” [red handwritten label] (SHNU) . Paratypes. 7♂♂ 10♀♀, same data as for the holotype ( SHNU, cPut) ; 2♂♂ 6♀♀, same locality, 29.IV.2019, Cheng, Miao, Xia & Zhang leg. ( SHNU) .

Description. Brachypterous (Figs 5, 6); body dark brown with faint bronze tint, each elytra with an orange spot near lateral margin. Antennae, maxillary palpi and legs yellowish brown except antennal club infuscate. Labrum brownish.

BL: 2.8–3.8 mm, FL: 1.5–1.8 mm.

HW: 0.69–0.81 mm, PL: 0.55–0.68 mm, PW: 0.53–0.62 mm, EL: 0.50–0.57 mm, EW: 0.62–0.74 mm, SL: 0.35–0.39 mm.

Head 1.01–1.13 times as wide as elytra; interocular area with two deep longitudinal furrows, median portion convex, extending beneath the level of inner eye margins; punctures round, slightly larger and sparser on median portion than those near inner margins of eyes, diameter of large punctures as wide as apical cross section of antennal segment II; interstices between punctures smooth, mostly narrower than half the diameter of punctures except those along the midline of the posteromedian portion and few at the bottom of longitudinal furrows, which may be slightly narrower than the diameter of punctures. Paraglossae oval.

Pronotum 0.98–1.13 times as long as wide; disk relatively even without distinct median longitudinal furrow; punctures round and slightly confluent, different in size, slightly larger than those of head in average; interstices smooth, much narrower than half the diameter of punctures except for few near the actual middle, which may be as wide as the diameter of punctures.

Elytra 0.73–0.88 times as long as wide; disk relatively even; punctures round to elliptic, more or less longitudinally confluent, slightly larger than those of pronotum in average; interstices partially with indistinct microsculpture, distinctly smaller than half the diameter of punctures.

Legs with tarsomeres IV strongly bilobed.

Abdomen cylindrical; segment III with paratergites very narrow and almost impunctate, segments IV–VI with tergites and sternites totally fused, though traces of paratergites present in basal fifth to sixth of each segments; posterior margin of tergite VII with indistinct apical membranous fringe; punctation of tergites III–VIII sparse and shallow, gradually becoming smaller posteriad; interstices smooth, mostly wider than diameter of punctures except those on basal impressions of tergites III–V, which may be narrower than half the diameter of punctures.

Male. Sternite VII indistinctly emarginated at middle of posterior margin with a flatten area before it; sternite VIII ( Fig. 9 ) with distinct triangular emargination at middle of posterior margin; sternite IX ( Fig. 10 ) with distinct apicolateral projections, posterior margin serrate. Aedeagus ( Figs. 12, 13 ) with apical sclerotized portion subtriangular, apex roundly prominent with few short setae; sclerotized expulsion clasps large, jointed; median longitudinal bands with ventral bands each long, narrow, dorsal bands each short and relatively broad, lateral longitudinal bands short; copulatory tube stout; parameres longer than median lobe, each with 10–12 setae on apico-internal margins.

Female. Sternite VIII ( Fig. 11 ) entire; spermatheca ( Fig. 14 ) weakly sclerotized and coiled at first bend.

Bionomics. All specimens were collected by sifting leaf litters of Rhododendron sp. near roots of living Poaceae sp. and Rosa sp.

Remarks. The species belongs to Stenus cirrus group. Externally, it resembles S. luoleeorum Rougemont, 2017 from Hongkong, S. huanghaoi Tang & Li, 2008 (in Tang, Zhao & Li, 2008) from Guangdong, S. xuwangi Tang & Li, 2008 (in Tang, Zhao & Li, 2008) from Guangdong, and S. nanlingmontis Tang & Li, 2008 (in Tang, Zhao & Li, 2008) from Guangdong, but can be easily distinguished from them by elytra distinctly shorter than length, from S. luoleeorum also by interstices of abdominal tergites smooth without microsculpture.

Distribution. China (Guangdong).

Etymology. The specific name is derived from the type locality of this species.

Figures

FIGURES 1–6. 1. A living Stenus abdominalis abdominalis 2. A living S. bivulneratus 3. Mating of living S. flavidulus paederinus 4. A living S. frater 5. Habitat of S. wutongshanus near mountain summit 6. A living S. wutongshanus.

FIGURES 7, 8. Habitus of Stenus wutongshanus 7. Dorsal view 8. Ventral view. Scale bars = 1 mm.

FIGURES 9–14. Stenus wutongshanus 9. Male sternite VIII 10. Male sternite IX 11. Female sternite VIII 12, 13. Aedeagus 14. Valvifers and spermatheca. Scale bars = 0.25 mm.