Stenus hujiayaoi Liu and Tang

Liu, Sheng-Nan & Tang, Liang, 2017, Seven new species of the Stenus cirrus group (Coleoptera, Staphylinidae) from Guangxi, South China, Zootaxa 4268 (2), pp. 238-254 : 239-240

Stenus hujiayaoi Liu and Tang , new species

( Figs 1, 2 , 15–22 )

Material examined. CHINA: Guangxi: Holotype: ♂, Mt. Mao’ershan , Gaozhai, 25°51'N 110°29'E, alt. 450 –600 m. 21.VII.2012, HU Jia-Yao & SONG Xiao-Bin leg. (SHNU). Paratupes : 9♂♂ 10♀♀, same data as for the holotype. ( SHNU) ; 1♂ 1♀, same data as for the holotype. (cPut) ; ♂, same data as for the holotype, but 25.VII.2012, HU Jia-Yao leg. ( SHNU) ; 3♂♂ 9♀♀, Mt. Mao’ershan , alt. 450 –650 m. 25.VII.2012, HU Jia-Yao & SONG Xiao- Bin leg. (SHNU); 3♂♂ 3♀♀, Xing’an County, Mao’ershan Mt. , 25°48'N 110°24'E, alt. 1500 m. 24.VII.2012, ZHU Jian-Qing leg. ( SHNU) .

Description. Brachypterous; body blackish, each elytron with a very large elongate yellow spot near lateral margin, which is about 4/5 as long as and 1/2 as broad as the respective elytron. Antennae, maxillary palpi and legs yellowish brown except antennal club infuscate. Labrum reddish brown.

BL: 5.3–6.2 mm, FL: 2.4–2.8 mm.

HW: 0.94–1.05 mm, PL: 0.74–0.81 mm, PW: 0.74–0.79 mm, EL: 0.87–0.97 mm, EW: 0.87–1.03 mm, SL: 0.64–0.72 mm.

Head 0.99–1.09 times as wide as elytra; interocular area with two deep longitudinal furrows, median portion convex, reaching 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 about 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 posterior median portion, which may be wider than the diameter of punctures. Paraglossae oval.

Pronotum 1.00–1.05 times as long as wide; disk uneven, with distinct median longitudinal furrow which is about 1/2 the length of pronotum; punctures round, more or less confluent, of similar size to those of head; interstices smooth, much narrower than half the diameter of punctures except for those in the middle of the median longitudinal furrow, which may be twice as wide as the diameter of punctures.

Elytra 0.94–1.00 times as long as wide; disk relatively even; punctures round to elliptic, moderately confluent, larger than those on pronotum; interstices smooth, distinctly smaller than half the 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 apical membranous fringe; punctation of tergites III–VIII sparse and shallow, gradually becoming smaller posteriad; interstices smooth, varied from smaller to larger than diameter of punctures.

Male. Sternite VIII ( Fig. 15 ) with distinct triangular emargination at middle of posterior margin; sternite IX ( Fig.17 ) with long apicolateral projections, posterior margin serrate; tergite X ( Fig. 16 ) with posterior margin convex. Aedeagus ( Fig. 18 ) with apical sclerotized portion of median lobe triangular; expulsion clasps large, strongly sclerotized; parameres distinctly longer than median lobe, each with 15–17 setae on apico-internal margins.

Female. Sternite VIII ( Fig. 20 ) entire; tergite X ( Fig. 22 ) convex; spermatheca ( Fig. 21 ) with basal porch distinct, the rest duct undetected.

Distribution. China (Guangxi).

Remarks. This new species is similar to S. maoershanus Pan, Tang & Li, 2012 from Guangxi and S. nanlingmotis Tang Zhao & Li, 2008 from Guangdong, but it can be easily distinguished from the latter two species by the broader and deeper pronotal furrow, the larger elytral spots, the larger body size and different sexual characters.

Etymology. This species is named in honor of Dr. HU Jia-Yao who collected some specimens of the new species.

Figures

FIGURES 1 – 2. Dorsal habitus of Stenus hujiayaoi sp. n. Scale bars: 1 mm.

FIGURES 15 – 22. Diagnostic features of Stenus hujiayaoi. 15. Male sternite VIII. 16. Male tergites IX – X. 17. Male sternite IX. 18 – 19. Aedeagus, in dorsal view. 20. Female sternite VIII. 21. Valvifers. 22. Female tergites IX – X. Scale bars: 0.25 mm.