Tianeotrechus Tian & Tang

Tian, Mingyi, Huang, Sunbin, Wang, Xinhui & Tang, Mingruo, 2016, Contributions to the knowledge of subterranean trechine beetles in southern China's karsts: five new genera (Insecta, Coleoptera, Carabidae, Trechinae), ZooKeys 564, pp. 121-156 : 133-134

Taxon classification Animalia Coleoptera Carabidae

Tianeotrechus Tian & Tang gen. n.

Type species.

Tianeotrechus trisetosus Tian & Tang, sp. n. (Bahao Dong, Tian’e County, Guangxi).

Diagnosis.

Medium-sized cave beetles, with typical aphaenopsian head, reduced frontal furrows, quadridentate right mandible, evident labial suture, bisetose mentum, robust pronotum, invisible propleura from above though which is tumid, and strongly covex elytra which have three pairs of dorsal setiferious pores.

Generic characteristics.

Medium-sized and semi-aphaenopsian trechines, eyeless, unpigmented and apterous; head evidently aphaenopsian, with incomplete frontal furrows and a somewhat elongated head, with two pairs of supra-orbital pores; mandibles developed, right mandible quadridentate, molar and retinacular teeth more developed than premolar tooth which is bifid (Fig. 9A); mentum and submentum well separated by labial suture; mentum bisetose, distinctly concave, mental tooth short and thick, bifid apically; submentum provided with a row of seven setae, median one minute and much shorter than others; antennae fairly short, reaching a little beyond middle of elytra; pronotum robust, longer than wide, sides expanded at apical third, making lateral suture invisible from above; posterior lateromarginal setae absent; elytra strongly convex, nearly as long as fore body (including mandibles), humeral shoulders roundly angulate, lateral sides smooth; striae reduced but more or less traceable; three dorsal and the pre-apical setae present; marginal umbilicate series not aggregate, only 2nd pore close to marginal gutter; 1st pore of humeral group shifted backward and about level to 5th stria, a little behind 2nd; 4th distant from 3rd; both pores of middle group lying close to each other; legs moderate for cave trechines, tibiae without longitudinal furrows externally; protarsi in male not modified; ventrite VII bisetose in male, 4-setose in female; male genitalia minute, well-sclerotized, moderately curved in middle part, apex slightly raised and pointed in lateral view; basal part quite large, sagittal aileron present; inner sac armed with a thin and scale-covered copulatory piece; parameres large but short, each bearing three long setae at apex.

Remarks.

It is not easy to determine the taxonomic position of this new genus. Several generically important characters of Tianeotrechus gen. n. do not exist in the other genera of Chinese Trechini : a quadridentate right mandible, invisible pronotal lateral borders and the presence of three dorsal pores on each elytron. We hope more discoveries in the near future will be able to shed additional light to clarify this problem.

Etymology.

Tian’e + Trechus, in reference to the provenance of the type species from Tian’e County. Gender masculine.

Range.

China (northern Guangxi) (Fig. 5d).