Nitidotachinus excellens (Bernhauer, 1938)

Zheng, Dan-Lin, Li, Li-Zhen & Zhao, Mei-Jun, 2014, Review of Nitidotachinus Campbell (Staphylinidae, Tachyporinae) from Mainland China, ZooKeys 447, pp. 87-107 : 93-96

Taxon classification Animalia Coleoptera Staphylinidae

Nitidotachinus excellens (Bernhauer, 1938) Figs 1 G–H, 8, 9

Tachinus excellens Bernhauer, 1938: 23; Li and Chen 1990: 19; Li 1992: 55.

Tachinus exceliens : Li 1993: 43.

Tachinus sawadai Watanabe & Shibata, 1961: 36; Campbell 1993: 531.

Nitidotachinus excellens : Campbell 1995: 45; Herman 2001: 850; Smetana 2004: 340; Schülke 2005: 170.

Nitidotachinus excellens concolor Schülke, 2000: 907. syn. n.

Specimens examined.

China: 5 males, 5 females Mt. Xiaowutai Reserve (alt. 1300-1600m), Wei County, Hebei Prov., 22.VIII.2005, Li-Zhen Li leg.; 1 male, 1 female, Jinhekou (alt. 1300m), Wei County, Hebei Prov., 23.VIII.2005, Li-Zhen Li leg.; 11 males, 10 females, Labahe Reserve (alt. 1900m), Tianquan County, Sichuan Prov., 29.VII.2006, Jia-Yao Hu and Liang Tang leg.; 1 male, 5 females, Labahe Reserve (alt. 2000m), Tianquan County, Sichuan Prov., 30.VII.2006, Jia-Yao Hu and Liang Tang leg.; 1 males, 1 females, Foping Conv. (alt. 1400-1800m), Shaanxi Prov., 19.VII.2004, Jia-Yao Hu, Liang Tang and Li-Long Zhu leg.; 1 male, ditto, but (alt.1250-1400m), 18.VII.2004; 1 female, Yangjiaping (alt.830m), Zhulu Couty, Hebei Prov., 4.VIII.2005, Li-Zhen Li leg.; 1 female (paratype), with labels as: CHINA: S-Sichuan 1999, Ya’an Prefecture, Shimian Co., Xiaoxiang Ling, Pass zw. Shimian u., Ganluo, 27 km SE Shimian, 29°03N, 102°31E, 2450m, Quellsumpf, Bachufer, 8. VII., leg. M/ Schülke (white) / Sammlung M. Schülke, Berlin (green) / PARATYPUS, Nitidotachinus exellens subspec. concolor n., det. M. Schülke, 2000 (red).

Description.

Body (Fig. 1 G–H) medium in size, 4.5-5.9 mm (total length); 3.1-3.4 mm (length of forebody). Color dark brown with shine; the first and second segments of antennae, mouthparts, sides and posterior margin of pronotum, posterior margins of elytra, and legs yellowish red.

Head 0.48 times as wide as pronotum. Surface finely and sparsely punctate, with dense and coarse microsculpture consisting of irregular meshes and transverse wave lines. Antennae moderately long, reaching the middle of elytra; the relative length of each segment from base to apex: 11.5: 7.0: 15.0: 12.0: 14.0: 14.5: 13.0: 13.0: 13.0: 13.0: 16.0; the tenth segment 1.73 times as long as wide. Maxillary palpus with relative lengths of 4th and 3rd segments: 15.5: 8.0.

Pronotum 0.65 times as long as wide; microsculpture shallower and punctures much finer and sparser than those on head.

Elytra in sutural length 0.72 times as long as wide; 1.15 times as long as the median length of pronotum; punctures and microsculpture a little courser than those on pronotum.

Abdomen sparsely and finely punctate and pubescent, with minute microsculpture only at sides of third tergite.

Male: Fore tarsal segments I–IV dilated; the relative lengths of hind tarsal segments from base to apex: 14.0: 7.5: 5.0: 4.0: 10.0. Eighth tergite (Fig. 8C) 4-lobed; inner lobes separated from each other by a V-shaped emargination and distinctly longer than outer lobes. Sixth sternite (Fig. 8A) without short peg seta. Seventh sternite (Fig. 8B) subtriangularly depressed at middle in posterior part, roundly emarginated at middle in apical margin, symmetrically covered with sparse short peg setae in the depression before posterior margin, densely covered with long black spiniform setae on posterior margin. Eighth sternite (Fig. 8D) 2-lobed, deeply incised between two lobes, the depth 0.35 times as long as the median length of sternite. Aedeagus (Figs 8 G–H) medium in size; parameres shorter than median lobe, each with a spindly projection near apex.

Female (Fig. 8): Fore tarsal segments I–IV normal. Eighth tergite (Fig. 8E) 4-lobed; inner lobes relatively shallowly separated with each other, distinctly longer than outer lobes. Eighth sternite (Fig. 8F) 6-lobed; inner lobes almost fused with each other, slightly emarginate at middle in posterior margins.

Distribution.

China (Hebei, Shaanxi, Sichuan, Heilongjiang, Jilin, Liaoning, Beijing); Japan; Far East Russia; Korea.

Remarks.

This new species is similar to Nitidotachinus impunctatus and Nitidotachinus japonicus . But can be easily separated from them by the different shape of aedeagal parameres.

Comments.

Nitidotachinus excellens concolor was described by Schülke in 2000 from Xiaoxiang Ling, Shimian, Ya’an, Sichuan Province. The characters separating it from the nominal subspecies were mentioned to be almost total black pronotum, darker elytra and inner emargination of female eighth tergite slightly deeper and wider. Though a paratype (Fig. 1H) of it also shows the broad yellowish brown lateral margins on pronotum. With more material collected in recent years, those diagnosis characters mentioned above are now considered as variability within Nitidotachinus excellens and the distribution gap between two subspecies are totally filled. Thus Nitidotachinus excellens concolor has to be synonymized with Nitidotachinus excellens , which is also fully agreed by M. Schülke (personal communication).