Tianzhuaphaenops, Zhao, Danyang & Tian, Mingyi, 2016

Zhao, Danyang & Tian, Mingyi, 2016, A new genus and species of troglobitic ground beetle from eastern Guizhou, Southwest China (Coleoptera: Carabidae: Trechinae), Zootaxa 4097 (3), pp. 434-441 : 435-437

Tianzhuaphaenops n. gen.

Type species: Tianzhuaphaenops jinshanensis n. sp. (Cave Jinshan Rongdong, Tianzhu County, eastern Guizhou Province)

Generic diagnosis. Medium-sized, aphaenopsian, yet not too highly modified morphologically trechine ( Fig. 1 ); eyeless, unpigmented and apterous; slender and elongate body, with slender and long appendages; sparse hairs covered the head laterally; longer and equally sparse hairs covered the pronotum and short pubescence on elytra; head elongate, much longer than wide, longer than prothorax; frontal furrows short, with two pairs of supra-orbital pores; right mandible bidentate; labial suture clear; mentum bisetose, tooth short and bifid at apex; submentum 10- setose; antennae long, nearly reaching the elytral apex; propleura more or less visible from above; pronotum elongate, longer than wide, widest near the front; presence of two pairs of lateromarginal setae, front and hind angles angular; elytra elongate-ovate, strongly convex though depressed medially near base, shoulders distinct and rounded, lateral margins ciliated throughout; striae faintly impressed; pre-apical pores and two dorsal pores present on each elytron; humeral group of marginal umbilicate pores not aggregated; protibia without an external longitudinal groove; 1st protarsomere modified in male; ventrite VII with one pair of setae in male, two pairs in female; male genitalia well developed, almost straightly stretched, with narrow parameres and bisetose at each apex ( Fig. 2 ).

Discussions. It is not easy to determine the taxonomic position of Tianzhuaphaenops n. gen. within cavedwelling trechines in China as of yet. Doubtless, it falls into the Guizhaphaenops- Qianotrechus- Qianaphaenops complex. Regarding its bidentate right mandible, Tianzhuaphaenops is probably close to Qianotrechus , but differs from the latter by having only protarsomere 1 modified in males (tarsomeres 1 and 2 are modified in the latter); longer antennae extending beyond the elytral apex (shorter, and not reaching the elytral apex in the latter); legs longer and more slender; labial suture well-defined (completely disappeared in the latter); and aedeagus straightly stretched, with narrow and apically bisetose parameres (aedeagus more or less arcuate, parameres wider and having more setose at apex in the latter). Compared with Guizhaphaenops , which also has a bidentate right mandible and only protarsomere 1 modified in males, Tianzhuaphaenops is more aphaenopsoid with a quadrate pronotum (versus arcuate-sided in the latter), and a well-defined labial suture that well separates mentum from submentum (versus completely disappeared in the latter). Tianzhuaphaenops shares the following three main characteristics with Qianaphaenops : clearly visible labial suture, the presence of posterior lateromarginal setae on pronotum, and preapical setae on elytra. It is distinguished from the latter genus by: bidentate right mandible (versus tridentate in the latter), having only protarsomere 1 modified in males (versus protarsomeres 1 and 2 modified in the latter), and longer, more slender antennae that extend over the elytral apex (versus shorter and not reaching elytral apex in the latter).

Etymology. Tianzhu + Aphaenops , to indicate that this genus occurs in Tianzhu County, eastern Guizhou Province, Southwest China; gender masculine.

Range. China (eastern Guizhou) ( Fig. 3 ).

Figures

FIGURE 1. Habitus of Tianzhuaphaenops jinshanensis n. gen., n. sp., male, holotype (chaetotaxy indicated by white points)

FIGURE 2. Male genitalia of Tianzhuaphaenops jinshanensis n. gen., n. sp. (a. median lobe and parameres, lateral view; b. median lobe, dorsal view)

FIGURE 3. Distribution of Tianzhuaphaenops jinshanensis n. gen., n. sp.