Stenochinus apiciconcavus, Yuan, Cai-Xia & Ren, Guo-Dong, 2014

Yuan, Cai-Xia & Ren, Guo-Dong, 2014, Two new species of the Stenochinus amplus species-group from China (Coleoptera, Tenebrionidae, Stenochiini), ZooKeys 416, pp. 67-76 : 69-71

Taxon classification Animalia Coleoptera Tenebrionidae

Stenochinus apiciconcavus sp. n. Figs 1, 7, 11-12, 17

Type material.

Holotype: ♂, China, Shaanxi, Nanzheng county, Beiba town, 20.vi.2005, Yi-Bin Ba leg. (MHBU).

Diagnosis.

This new species is similar to Stenochinus cylindricus (Gebien, 1914), but can be distinguished from the latter by the pronotum moderately projecting anteriorly, with emargination in middle of anterior margin; scutellum subrectangular; maxillary palpomere IV strongly expanded (in Stenochinus cylindricus , pronotum strongly projecting anteriorly, without emargination at anterior margin (Figs 4, 6); scutellum subquadrate; maxillary palpomere IV moderately expanded). It also resembles Stenochinus wakoi Masumoto & Akita, 2002, but differs in the following characters: antennomeres VIII–XI wider than long; pronotum with emargination in middle of anterior margin; scutellum subrectangular, glabrous (in Stenochinus wakoi , antennomeres VI–XI wider than long; pronotum without emargination at anterior margin; scutellum subquadrate, covered with scale-like hairs on both sides).

Etymology.

The specific name is derived from the Latin apici [apex] + concavus[concave], a reference to the pronotum with an emargination in middle of anterior margin.

Description.

Male (Fig. 17). Body length 10.3 mm, elongate, subcylindrical. Head, elytra and legs dark reddish brown, antennae reddish brown, pronotum dark brown. Scale-like hairs on the surface pale golden. Head transversely subelliptical, surface densely punctate; clypeus truncate at anterior margin, clypeogenal suture grooved, frontoclypeal suture invisible; genae weakly raised, with rounded outer margins; frons wide, distance between eyes 2.56 times as wide as transverse diameter of an eye in dorsal view. Eyes medium-sized, weakly protruding, each side with a groove along inner and posterior margins. Antennae (Fig. 7) clavate, antennomeres VIII–XI each wider than long, antennomeres XI ovate, ratio of the length of antennomeres II–XI as 0.12: 0.18: 0.09: 0.09: 0.07: 0.08: 0.07: 0.10: 0.08: 0.22. Maxillary palpomere IV strongly expanded. Pronotum (Fig. 1) 1.13 times as long as wide, widest in middle; anterior margin with a distinct emargination in middle; posterior margin weakly bisinuate, with deep emar gination in middle; both sides steeply inclined downward, lateral margins sinuate before posterior angles; anterior angles acute and directed anteriad, posterior angles acute and directed postero-laterad; disc subelliptically projecting in anterior parts, this projecting area distinctly impressed, surface roughly and deeply punctuate, punctures often fused with one anonther. Scutellum subrectangular, glabrous. Elytra 2.5 times as long as wide, widest at apical 1/3, 2.76 times as long as and 1.25 times as wide as pronotum; dorsum convex but flattened in lateral view; disc with rows of subquadrate punctures, which are larger and deeper anteriorly, each puncture with a granule on each lateral margin; intervals somewhat transversely wrinkled, weakly ridged in lateral parts, scale-like hairs on the intervals shorter than those on pronotum. Ventral side covered with dense punctures and scale-like hairs, which distinctly shorter than those on pronotum. Legs relatively short, ratio of the lengths of metatarsomeres I–IV as 0.45: 0.24: 0.17: 0.69. Male genitalia (Figs 11-12) curved in middle in lateral view, 1.94 mm long, 0.43 mm wide; apicale 0.71 mm long, weakly curved in lateral view.

Female: Unknown.