Adiscus punctithorax Medvedev, 2008

Duan, Wen-Yuan & Zhou, Hong-Zhang, 2022, Revision of the genus Adiscus Gistel, 1857 (Coleoptera: Chrysomelidae, Cryptocephalinae) from mainland China, Zootaxa 5096 (1), pp. 1-80 : 65-68

Adiscus punctithorax Medvedev, 2008

(Figs 27-1; 27-2)

Adiscus punctithorax Medvedev, 2008: 200 (type locality: Anhui; type deposited: NHMB); Schöller et al., 2010: 608 (catalogue).

Material examined. China: Paratype: 1 male, “ Anhui, Dabeishan , 65km SW Huoshan / 1400 m / 21–24. VI. 1960 / coll. Bolm lgt // PARATYPE ”. ( ZIN) .

Redescription. Measurements. Male. BL = 2.12–2.54 mm, BW = 1.59–1.95 mm, HL = 0.83 mm, HW = 0.76 mm, PL = 0.82 mm, PW = 1.67 mm, PA = 105°, EL = 1.76 mm, EA = 120°, AL = 2.31 mm, AW = 0.73 mm.

Body (Fig. 27-1A) short ovate. Head fulvous, antennomeres 1–5 fulvous, 6–11 darkish brown. Pronotum fulvous, basal margin black. Elytra black. Legs including coxae fulvous. Prosternum and metaventrite yellowish brown, ventral side of abdomen largely yellowish brown.

Head dull, densely and coarsely punctate in middle and along side, partly strigose on frons. Eyes reniform; superior eye-lobes separated by same distance as antennal insertions. Clypeus semicircular, with slightly stronger punctures than those on upper portion, anterior margin arched and emarginated. Antennae long, reaching middle of elytra; scape clubbed, pedicel oblong, about half as long as scape, antennomeres 3–5 slender, pedicel and 3–5 about equal in length, 6 longer, but not thickened, 10 about four times as long as broad.

Pronotum (Fig. 27-1A) convex and shiny, base much broader than apex, basal width about twice pronotal length. Anterior margin nearly straight. Posterior margin sinuate with fine serration, and produced into an obtuse angle of about 105° at middle. Disc evenly convex, finely and rather closely and coarsely punctures, with smooth narrow interspaces.

Elytra (Fig. 27-1A) as broad as long, humeri somewhat prominent, glabrous. Disc punctate, with 11 regular striae, intervals with scattered minute punctures, puncture striae irregular on apical slope. Epipleural lobe large, lateral margins distinctly expanded ventrally with rounded lobe at basal 1/4 of elytron, with both lobe sides forming angle of 120°.

Venter clothed with shortly silvery pubescence and punctures. Prosternum trapezoidal, lateral ridge elevated, straight in lateral view, anterior and posterior margins concave, hind angles not produced. Mesoventrite broad, about twice as wide as long Pygidium with dense punctures and short pubescence. First segment of fore and middle tarsi moderately widened.

Aedeagus. (Figs. 27-1D–F; 27-2) Median lobe elongate, about 3.1 times as long as wide, nearly parallel-sided. Apex of median lobe slightly narrower than middle, acute at apex, moderately curved in lateral view, with several setae on each side of apex, indistinctly punctate on ventral side of apical part. Median orifice with median sclerite bending inwards above surface. Inner sac rather narrow, cylindrical, twisted. Tegmen Y-shaped, weakly sclerotized, almost translucent.

Distribution. China (Anhui).

Diagnosis. This species is similar to A. annulatus , but the elytra are yellowish brown with a black band.