Sinaphaenopoides Tian & Huang & Jia 2023, n. gen.

Sinaphaenopoides n. gen.

Type species: Sinaphaenopoides zhaoyiae n. sp. (Zhongguo Dong, Chenzhou, Hunan)

Generic characteristics. Medium-sized for cave trechines; aphaenopsian, more or less similar to Sinaphaenops Uéno & Wang, 1991; body moderately elongate, fore body as long as elytra; head covered with sparse setae, pronotum and elytra glabrous, but head with a few sparse setae on genae. Head much longer than wide, side tumid, neck short, constriction short; presence of three pairs of supraorbital setiferous pores; frontal furrows short, ended before middle of head; frons flat, vertex strongly convex; clypeus 6-setose; right mandibular tooth bidentate; mentum and submentum fused; mentum bisetose, base largely concave; tooth simple at apex; submentum with a row of 8 or 9 setae; 2 nd labial palp bisetose on inner margin; antennae thin and long, extending to apical margins of elytra; scape longer than pedicel. Prothorax longer than wide, strongly tumid, making the propleura visible from above; pronotum longer than wide, with two pairs of latero-marginal setae, hind angle forwardly shifted, sharp; disc moderately convex, base as long as front. Elytra elongated ovate, widest at about apical 2/5; humeral angles completely rounded; lateral margins smooth and glabrous throughout; disc strongly convex, striae obsolete though more or less traceable, intervals slightly convex; apical striole absent; presence of two dorsal and the preapical pores; only 2 nd marginal umbilicate pore near marginal gutter; humeral set not aggregated, 1 st pore inwardly and backwardly shifted, median set moderately separated each other. Fore tibiae not sulcate longitudinally.

Remarks. Sinaphaenopoides n. gen. is similar to the genus Sinaphaenops Uéno & Wang, 1991 ranged in Guizhou and northern most Guangxi, in body shape as well as in the chaetotaxy. But there is a large geographical gap between them. For example, the cave Zhongguo Dong, the locality of Sinaphaenopoides, is about 500 km from the cave Laji Dong in Libo Xian, southeastern Guizhou, which is a locality of S. wangorum Uéno & Ran, 1998, the eastern most for a Sinaphaenops species (Uéno & Wang 1991, Uéno & Ran 1998, Chen et al. 2017). However, Sinaphaenopoides n. gen. harbours several different characteristics of generic importance from Sinaphaenops apart from less elongate and thinner legs and antennae, such as: (1) head with three pairs of frontal setiferous pores in Sinaphaenopoides n. gen., vs. only one or two pair(s) of frontal setiferous pores in Sinaphaenops; (2) scape of antennae longer than pedicel in Sinaphaenopoides n. gen. vs. shorter in Sinaphaenops; and (3) elytra moderately convex in Sinaphaenopoides n. gen., with striae more or less traceable, vs. elytra strongly convex and striae completely disappeared in Sinaphaenops. Probably, Sinaphaenopoides n. gen. is relative to the subgenus Dongaphaenops Deuve & Tian, 2014 within Sinaphaenops because they share the following characteristics: (1) Head sparsely setose, with shorter antennae which extending only at elytra apices; (2) mentum and submentum fused; and (3) pronotum with two pairs of latero-marginal pores. Phylogenetic analysis based on molecular data hinted that Dongaphaenops would be an independent lineage.

Etymology. Refers to the similarities between the new genus and Sinaphaenops. Gender masculine.

Range. China (Hunan) (Figure 1m).