Derops hainanus 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 : 54-57

Derops hainanus Zhao & Li sp. n. Figs 1A, 2

Type locality.

Hainan Prov., China

Type material.

(1 ♂). HOLOTYPE: ♂, labeled 'China: Hainan Prov. / Changjiang County / Bawangling Nature Reserve / 11.iv.2010, alt. 1,000 m / Zi-Wei Yin leg.'.

Description.

Measurements and ratios. BL: 4.23; FL: 2.89; HL: 0.46; HW: 0.78; PL: 0.85; PW: 0.93; EL: 1.59; EW: 1.13; SL: 1.31; ED: 0.37; TL: 0.17; HW/HL: 1.70; PW/PL: 1.09; EL/EW: 1.41; PW/HW: 1.19; EL/PL: 1.87; EW/PW: 1.22; ED/TL: 2.18.

This species is assigned to Derops longicornis group based on the following characteristics: elytra finely and densely punctured, not or little shiny; male sternite VII deep emarginated on the posterior margin, two additional granules fields next to the posterior margin with short, strong and blunt seta.

Body (Fig. 1A). Uniformly reddish black to reddish brown and moderately shining; mouthparts including maxillary and labial palpi, apical two and first two antennal segments, tarsi yellowish brown; pronotum, the rest of antennae and legs except for tarsi reddish brown; elytra light to dark brunneous. 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: 1.70), with shining punctures moderately coarse and dense, without microsculpture, and surface covered with short, sparse, fine yellowish brown pubescence, but almost deprived of pubescence close to neck. Eyes relatively large (ED/TL: 2.18) and slightly prominent laterad, postocular region gently arcuate and loosely contracted at neck. Antenna filiform and almost extending to the middle of elytra, all the segments with pubescence slightly dilated apicad, 1st segment robust, 2nd the shortest and as twice as broad, 3rd to 6th equal in both broad and distinctly longer than broad, 7th to 8th equal in both length and width, 9th to 10th equal in width, and 9th longer than 10th, 11th distinctly longer and narrower than 10th, excavated at the apex.

Pronotum obcordate and convex, slightly transverse (PW/PL: 1.09), distinctly broader than head (PW/HW: 1.19); expanded laterally in anterior one fifth, arcuate in anterior two-fifths and almost straight in posterior three-fifths, anterior angles bluntly angulate and invisible from above; posterior ones rectangular. surface on both sides with punctate as head, most interspaces between punctures somewhat less than diameters of punctures, covered with sparse, fine, moderately long, yellowish brown pubescence all over, without sculpture; providing with a shallow depression at the middle.

Elytra oblong, visibly longer than broad (EL/EW: 1.41), obviously longer (EL/PL: 1.87) and somewhat broader (EW/PW: 1.22) than pronotum; lateral sides nearly parallel, posterior margin emarginate at the middle, posterior angles broadly rounded; surface densely, fine punctate, more sparser than head and elytra, transverse distances between punctures mostly twice than diameters of punctures, and shorter pubescence than pronotum, without sculpture, possessing two shallow and longitudinal depressions, along suture and lateral side respectively; epipleura each bearing a fine longitudinal keel, which is abbreviated behind shoulder. Scutellum small and ligulate.

Abdomen subcylindrical, gradually tapering towards apex; 4th to 7th tergite each transversely depressed along the base, punctation relatively coarse before the depression; each superficially with densely short fine pubescence.

Male. Sternite VII (Fig. 2A) deeply, wide, almost “U” shaped medio-apical emargination, depth approximately two-sevenths of the length, and armed with six short blackish seta and a long, black seta on each side of the emargination; with field of about 15 granules on each side of emargination. Tergite VIII (Fig. 2B) with shallow medio-apical emargination and with two long, strong, black setae at each lateral margin apical third. Sternite VIII (Fig. 2C) wide and very deep, blunt triangular emargination at the middle of posterior margin, depth about two-fifths of the length, surface with two long, strong, black seta at each lateral margin. Genital organ (Fig. 2D, E) long oval, slightly sclerotized; with median lobe no longer than lateral lobes combined; viewed dorsally, lateral lobes elongate, symmetrical, evenly narrowed to obtuse apices; viewed laterally, lateral lobes hardly bent ventrally, apical portion slightly barbed.

Female. Unknown.

Distribution.

China: Hainan Prov.

Etymology.

The name of the new species is derived from that of the type locality.

Remarks.

The new species may be readily distinguished from the rest species of Derops longicornis group by the following characteristics: male sternite VII field of not exceeding the half of medio-apical emargination depth, while in other species exceeding the half of medio-apical emargination depth, and even extended to emargination apex.