Stenus zhangdinghengi Pan, Tang & Li

Pan, Yu-Hong, Tang, Liang & Li, Li-Zhen, 2012, Notes on the Stenus cirrus group, with description of two new species from China (Coleoptera, Staphylinidae), ZooKeys 169, pp. 61-77 : 63-66

Stenus zhangdinghengi Pan, Tang & Li sp. n. Figs 5 –631– 40

Type material.

Holotype:CHINA: Guangxi Prov.: ♂, Lingui County, Huaping Nature Reserve, Anjiangping, alt. 1400-1700 m, 14.VII.2011, PENG Zhong leg. (SHNU). Paratypes:CHINA: Guangxi Prov.: 4♂♂, 7♀♀, Lingui County, Huaping Nature Reserve, Anjiangping, alt. 1300-1700 m, 14-18.VII.2011, TANG Liang, HE Wen-Jia & PENG Zhong leg. (1♂, 1♀ in cPut, remainder in SHNU).

Description.

BL: 3.5-3.9 mm; FL: 1.6-1.8 mm.

HW: 0.72-0.79 mm, PW: 0.53-0.55 mm, PL: 0.55-0.60 mm, EW: 0.60-0.68 mm, EL: 0.59-0.66 mm, SL: 0.44-0.49 mm.

Brachypterous; body brownish except for the blackish head, anterior margin of labrum, antennae, maxillary palpi and legs yellowish brown, each elytron with an elongate ill-defined orange mark near lateral side, this mark 1/3 to 1/2 as long and about 1/3 to 2/5 as broad as the respective elytron.

Head 1.16-1.21 times as wide as elytra; interocular area with two broad longitudinal furrows, median portion convex dorsally, not reaching level of inner eye margins; punctation round and slightly confluent, uniform except for several large punctures at posterior part of median portion; diameter of large punctures about as wide as antennal segment II in cross-section, interstices between punctures smooth, mostly narrower than half the diameter of punctures, those along midline much wider, forming a broad impunctate line. Relative length of antennal segments from base to apex 12: 9: 20: 11: 10.5: 10.5: 9: 6.5: 7: 8: 10.5. Paraglossae oval.

Pronotum 1.05-1.09 times as long as wide, 0.81-0.88 times as wide as elytra; disk with shallow median longitudinal furrow about 1/2 the length of pronotum; punctures round and moderately confluent, smaller in size than largest punctures on head, interstices smooth, narrower than half the diameter of punctures.

Elytra 0.96-0.98 times as long as wide, distinctly constricted at base, lateral margins gently divergent posteriad; disk almost even; punctures round to elliptic, uniform, slightly coarser than those of pronotum, interstices smooth, narrower than half the diameter of punctures.

Legs with hind tarsi 0.72-0.78 times as long as hind tibiae, tarsomere IV strongly bilobed.

Abdomen cylindrical; paratergites very narrow and smooth, present only at abdominal segment III, tergite VII with indistinct palisade fringe; punctation of tergite III–VIII sparse and shallow, gradually becoming finer posteriad, interstices smooth, varying from narrower to much wider than diameter of punctures.

Male. Sternite VII with shallow emargination at middle of posterior margin and a depression before it; sternite VIII (Fig. 31) with semi-circular emargination at middle of posterior margin; sternite IX (Fig. 32) with long apicolateral projections, posterior margin serrate; tergite X (Fig. 33) with posterior margin convex. Aedeagus (Fig. 34) with apical sclerotized portion of median lobe pointed at apex; expulsion hooks (Fig. 36) very large; parameres longer than median lobe, slightly swollen at apex, each with about 14 short setae at apico-internal margins.

Female. Sternite VIII (Fig. 37) with posterior margin entire; tergite X (Fig. 38) with posterior margin convex. Valvifers (Fig. 39) each with large apicolateral tooth; sclerotized spermatheca as in Fig. 40.

Distribution.

China (Guangxi Province: Huaping).

Diagnosis.

The new species resembles Stenus huanghaoi Tang & Li, 2008, with which it shares the faint elytral marks, but it may be distinguished by the heterogeneous punctation of the frons (in Stenus huanghaoi always similar in size), the shallower pronotal punctation (especially in the median furrow) and smaller body size (in Stenus huanghaoi BL: 3.9-4.5 mm).

Etymology.

This species is named in honor of Mr. Zhang Ding-Heng, administrator of the Huaping Nature Reserve, who provided help in various ways during our field work.

Biological notes.

All the specimens were collected by sifting the leaves of bamboo and broad-leaved shrubs in a thick forest (Fig. 50).