Derops yunnanus Zhao & Li

Zhao, Jie-Qiong & Li, Li-Zhen, 2013, New data on the genus Derops Sharp (Coleoptera, Staphylinidae, Tachyporinae) from China with description of two new species, ZooKeys 317, pp. 53-67 : 58-60

Derops yunnanus Zhao & Li sp. n. Figs 1B, 3

Type locality.

Yunnan Prov., China

Type material.

(6 ♂♂, 2 ♀♀). HOLOTYPE: ♂, labelled 'China: Yunnan Prov. / Xianggelila County / Hutiaoxia Nature Reserve / Jinxing Village / 22.iv.2005, alt. 2,300 m / Hao Huang leg.'; PARATYPES: 4 ♂♂, 2 ♀♀, same label data as holotype; 1 ♂, same, but ‘22.iv.2005.’.

Description.

Measurements and ratios. BL: 4.34-4.50; FL: 2.84-3.11; HL: 0.45-0.46; HW: 0.72-0.83; PL: 0.85-0.89; PW: 0.93-0.95; EL: 1.39-1.50; EW: 1.22-1.33; SL: 1.06-1.22; ED: 0.28-0.31; TL: 0.11-0.15; HW/HL: 1.60-1.84; PW/PL: 1.07-1.09; EL/EW: 1.13-1.17; PW/HW: 1.14-1.32; EL/PL: 1.56-1.69; EW/PW: 1.28-1.40; ED/TL: 2.07-2.55.

This species is assigned to Derops nitidipennis group based on its distinctive rough and extensive puncturing; male sternite VII is emarginate just flat at the posterior margin, the additional fields consist of long, apically pointed peg-like setae.

Body (Fig. 1B). Uniformly piceous-black to black and moderately shining; mouthparts including maxillary and labial palpi, antennal segments and tarsi reddish brown. Body narrowly elongate, subparallel-sided and somewhat convex; sides of abdomen gradually narrowed from base to apex.

Head distinctly transverse and impressed, broader across eyes than long (HW/HL: 1.60-1.84), with shining punctures moderately coarse and dense, without microsculpture, and surface covered with long brown pubescence and almost glossy near neck. Eyes relatively large (ED/TL: 2.07-2.55) and prominent laterad, postocular region gently arcuate and loosely contracted at neck. Antenna filiform and exceeding the middle of elytra, all the segments with pubescence slightly dilated apicad, 1st segment longest, 2nd the shortest and as twice as broad, 1st to 4th equal in both broad and distinctly longer than broad, 5th to 9th equal in both length and width and length more than three times the width, 10th to 11th equal in both length and width and length at most twice the width, 11th excavated at the apex.

Pronotum obcordate and convex, slightly transverse (PW/PL: 1.07-1.09), distinctly broader than head (PW/HW: 1.14-1.32); expanded laterally widest in anterior one-third, arcuate in anterior two-thirds and almost straight in posterior third, anterior angles bluntly angulate and invisible from above; posterior ones almost rectangular. surface on both sides with shining moderately coarse and sparser punctate than those of head, most interspaces between punctures somewhat less than half of diameters of punctures, covered with sparse, fine, yellowish brown pubescence all over, without sculpture; providing with a shallow depression at the middle of anterior margin.

Elytra oblong, slightly longer than broad (EL/EW: 1.13-1.17), obviously longer (EL/PL: 1.56-1.69) and somewhat broader (EW/PW: 1.28-1.40) than pronotum; lateral sides nearly parallel, posterior margin emarginate at the middle, posterior angles broad ly rounded; surface densely, coarse punctate, more sparser, but shallower than head and elytra, transverse distances between punctures mostly one to 2.5 times than diameters of punctures, and longer pubescence than pronotum, without sculpture, possessing two shallow and longitudinal depressions, one on each side of suture and the other on each lateral side; epipleura each bearing a fine longitudinal keel, which is abbreviated behind shoulder. Scutellum small and ligulate, and with dense, yellowish brown pubescence.

Abdomen subcylindrical, gradually tapering towards apex; 4th to 7th tergite each transversely depressed along the base, surface uneven depression, and providing with moderately coarse and dense punctation before depression, fine and shining punctation after depression; each superficially with dense, short and fine pubescence.

Male. Sternite VII (Fig. 3A) shallow, wide medio-apical emargination, and armed with six short rigid blackish cilia and a long, black seta on each side of the emargination; with field of about 20 apically acute peg-like setae on each side of emargination. Tergite VIII (Fig. 3B) with shallow medio-apical emargination and with two long, strong, black setae at each lateral margin two-thirds. Sternite VIII (Fig. 3C) wide and very deep, blunt triangular emargination at the middle of posterior margin, emargination almost extending to the middle, surface with two long, strong, black seta at each lateral margin. Genital organ (Fig. 3D, E) long oval, slightly sclerotized, median lobe shorter than lateral lobes combined; lateral lobes elongate, symmetrical, expand in one half and narrowed to obtuse apices; viewed laterally, lateral lobes hardly bent ventrally, apical portion slender.

Female. Tergite VIII (Fig. 3F) deep, broadly, “U” shaped excised at the middle of posterior margin, one very long black seta at each lateral margin at about apical four-sevenths, almost extending the middle of tergite. Sternite VIII (Fig. 3G) broadly emarginate at the middle of posterior margin and fringed with seven yellowish pubescence at the latero-posterior parts, and respectively with two long, strong, black setae at each lateral margin in apical three-fifths and four-fifths.

Distribution.

China: Yunnan Prov.

Etymology.

The specific name is derived from “Yunnan”, the province of the type locality.

Remarks.

The new species is similar to Derops shuckburghae Rougemont described from Thailand, but it may be readily distinguished from the latter one by the following characteristics: head larger and relatively broader with HW/HL: 1.60-1.84 (1.54 in Derops shuckburghae ); elytra shorter than pronotum with EL/PL: 1.56-1.69 (1.72 in Derops shuckburghae ), and punctation larger and denser, transverse distances between punctures mostly one to 2.5 times than diameters of punctures (transverse distances 2 to 3 times greater than diameters of punctures in Derops shuckburghae ); male sternite VII with field of about 20 apically acute peg-like setae on each side of medio-apical emargination (only 6-7 peg-like setae in Derops shuckburghae ); aedeagus lateral lobes symmetrical, expand in one half and narrowed to obtuse apices (slightly asymmetrical, evenly narrowed to obtuse apices in Derops shuckburghae ); female tergite VIII excised broader in anterior, almost extending the middle of tergite (excised narrower in anterior, clearly not extending the middle of tergite in Derops shuckburghae ).