Brachytrycherus curviantennae, Chang, Ling-Xiao, Bi, Wen-Xuan & Ren, Guo-Dong, 2016

Chang, Ling-Xiao, Bi, Wen-Xuan & Ren, Guo-Dong, 2016, Two new species of Brachytrycherus Arrow, 1920 from China (Coleoptera, Endomychidae), ZooKeys 595, pp. 137-146 : 139-143

Taxon classification Animalia Coleoptera Endomychidae

Brachytrycherus curviantennae sp. n. Figs 3-4, 6

Type material.

Holotype, male, Xizang, Medog, 1500 m, 20.VIII.2013, Wen-Xuan Bi leg. (SHEM); Paratypes, 1 female, Xizang, Medgo, Beibeng, Gelincun, 3.VIII.2014, Wen-Xuan Bi leg. (MHBU); 1 female, Xizang, Medgo, Beibeng, Gelincun, 3.VIII.2014, Wen-Xuan Bi leg. (CBWX).

Etymology.

The name refers to the antennomere 3 distinctly outwardly curved.

Diagnosis.

Brachytrycherus curviantennae is similar to Brachytrycherus madurensis in appearance, but can be differentiate by antennomere 3 distinctly curved outwards, pronotum sides strongly curved, elytral maculae with front and hind margins emarginate.

Description.

Length 8.5-9.4 mm. Body broadly oval, approximately 1.6-1.8 times as long as wide; convex; shiny. Colour black with four red maculae on elytra.

Head. Antenna 11-segmented, long and rather slender, nearly 1/2 body length, with antennomeres 1-8 distinctly longer than wide; scape approximately 4.5 times as long as pedicel; antennomere 3 distinctly curved, and nearly as long as 4 and 5 combined; antennomere 4 as long as 5, antennomeres 5-8 gradually shorter; club composed of 3 antennomeres, broad and flat. Maxilla with terminal palpomere elongate, almost 2.0 times as long as palpomere 3, tapering anteriorly, truncate apically.

Thorax. Pronotum 2.0-2.4 mm long, 4.1-4.2 mm wide; widest near 1/2 of pronotal length; coarsely and densely punctate; lateral margins narrowly bordered, sides in male wavy and strongly curved; in female sides smooth and strongly curved,; front angles produced anteriorly, blunt; disc weakly convex, with two large round raised areas laterally; transverse wrinkle laterally; median furrow absent; lateral sulci linear, deep, extending to basal 1/3 of pronotal length; basal sulcus nearly straight, deep. Prosternal process moderately separates the procoxae; sides weakly curved outwardly, weakly truncate apically. Mesoventral process transverse, lateral margins widening apically and overlapping part of mesocoxae; posterior margin nearly straight. Elytra 6.0-7.1 mm long, 5.1-5.2 mm wide; 3.0 times as long as pronotum and 1.2-1.3 times as wide as pronotum, sides curved, widest near 1/2 length of elytron; densely and coarsely punctate; humeri rather prominent. Each elytron with two transverse, irregular in shape red maculae. Anterior elytral macula nearly cymbiform, anterior margin widely U-shaped and deeply emarginate, posterior margin weakly wavy. Posterior macula transverse, inversely cymbiform, anterior margin weakly wavy, posterior margin widely U-shaped and deeply emarginate. Protibiae in male with concavity on inner edge of apical 1/3, in female without concavity; mesotibiae abruptly curved from near apical 1/3 to apex, in female gently curved; metatibiae in male abruptly widened from near 1/3 length to apical 1/4, in female gently widened.

Abdomen with 5 ventrites in both sexes. Ventrite 5 with lateral margins gently converging posteriorly, posterior margin widely rounded medially in male; in female ventrite 5 lateral margins abruptly converging posteriorly, posterior margin truncate, nearly straight medially. Aedeagus (Figs 6) rather long, heavily sclerotized, straight. Median lobe branched apically; branch long and rather straight, gently rising from about basal 1/3 to apical 1/3, flat, acute and weakly reflexed apically. Tegmen placed basally, comparatively large, ring-shaped.

Biology and ecology.

The male was hand collected by simple searching, as it is active on branches at night (Fig. 7). Two females were collected by shaking the tree from a large clump of dead wood of Fagaceae plants (Fig. 8).