Tachinus (s. str.) oblongoelytratus Feng & Li

Feng, Ting, Schuelke, Michael & Li, Li-Zhen, 2013, A taxonomic revision of the silphaeformis species-group of the genus Tachinus Gravenhorst (Staphylinidae, Tachyporinae) from China, ZooKeys 359, pp. 53-99 : 75-77

Tachinus (s. str.) oblongoelytratus Feng & Li sp. n. Figs 6A, 6B, 9K, 10K, 12B, 13K, 16E, 19C, 20L, 22B

Type locality.

China, Sichuan, Emeishan.

Type material.

Holotype: ♂, CHINA: Sichuan Prov. Emeishan City, Mt. Emei, 17.vii.2003, Li-Zhen LI leg. (SNUC). Paratypes: 27 ♂♂, 14 ♀♀, same label data as the holotype (SNUC); 7 ♂♂, CHINA: Sichuan Prov. Emeishan City, Mt. Emei, 1.viii.2001, LI & ZHAO leg. (SNUC).

Description.

Measurements of males (holotype): BL 3.95-4.17 (4.17); FL 2.89-2.95 (2.95); PL 0.88-0.89 (0.88); EL 1.39-1.50 (1.50); SEL 0.10-0.12 (0.12); HW 0.82-0.84 (0.83); PW 1.38-1.40 (1.39); EW 1.55-1.57 (1.56); relative length of antennomeres I–XI: 23: 14: 15: 10: 13: 14: 15: 12: 14: 13: 26. Measurements of females: BL 4.61-4.89; FL 3.61-3.70; PL 0.89-1.00; EL 1.61-1.72; SEL 0.16-0.18; HW 0.88-0.90; PW 1.49-1.51; EW 1.78-1.83; relative length of antennomeres I–XI: 25: 14: 15: 8: 15: 14: 15: 13: 13: 15: 30.

Body (Figs 6A, 6B) dark brown to black; head, pronotal disc, elytra and abdomen black; mouthparts, basal four antennomeres, posterior margin of pronotum, posterior margins of posterior abdominal tergites and legs reddish brown.

Head slightly transverse, HW: PW = 0.58-0.61 (0.60); surface with sparse fine punctation, microsculpture consisting of fine striae. Antennomeres X shorter than wide.

Pronotum transverse, PL: PW = 0.59-0.67 (0.63); surface with punctation similar to that of head, microsculpture consisting of transverse striae.

Elytra: EL: PL = 1.56-1.70 (1.70), EL: EW = 1.56-1.70 (0.96), EW: PW = 1.11-1.14 (1.12) in males; EL: PL = 1.61-1.93, EL: EW = 0.88-0.97, EW: PW = 1.18-1.23 in females; apical margin broadly rounded; surface with punctation denser and coarser than that of pronotum, microsculpture consisting of fine transverse meshes.

Male. Sternite VII (Figs 9K, 10K) with semicircular emargination at posterior margin, apical margin bent ventrad, strongly projecting, with large area of coarse granules. Tergite VIII (Fig. 12B) with apical lobes almost fused, forming a sinuate apical margin. Sternite VIII as in Fig. 13K. Median lobe of aedeagus (Fig. 16E) broad and much longer than parameres, apical portion with paired projection.

Female. Elytra only slightly longer than in male, apical margins broadly rounded, only weakly produced near sutural angle. Tergite VIII (Fig. 19C) trilobed, median lobe triangular and broad, lateral lobes short, each with one long seta. Fimbriate median lobes of sternite VIII (Fig. 20L) separated by shallow emargination, sublateral lobes slightly shorter than median ones.

Etymology.

The specific name (adjective) is a combination of the Latin adjective “oblongus” and the Greek word “elytron”. It refers to the long elytra.

Remarks.

Males of this species can be separated from those of the other species of the group by the unique shape of the aedeagus, females by the long median lobe and the chaetotaxy of the lateral lobes (each with one long seta) of tergite VIII.