Adiscus daofuensis Duan & Zhou, 2022

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 : 7-10

Adiscus daofuensis Duan & Zhou , sp. nov.

( Figs 2-1; 2-2 )

Type locality. CHINA: Sichuan Province: Daofu .

Material examined. Holotype: male, CHINA: Sichuan Province: Daofu, Benglong , 3000 m, 12. VIII. 1983, coll. Shuyong Wang ( IZ-CAS) . Paratypes: CHINA: Sichuan Province: 1 male, 7 females, same data as holotype ( IZ-CAS) ; 1 female, Wenchuan, Yingxiu , 900 m, 1. VIII. 1983, coll. Shuyong Wang ( IZ-CAS) ; Gansu Province: 1 female, Wenxian, Bifenggou , 940–1500 m, 28. VII. 1999, coll. Jian Yao ( IZ-CAS) ; Henan Province: 1 female, Xinxian, Liankang Mountain , 19–21. VII. 2005, coll. Chao Gao & Jiliang Wang ( IZ-CAS) ; 1 male, Luoshandongzhai Reserve , 14–15. VII. 2005, coll. Chao Gao & Jiliang Wang ( IZ-CAS) .

Description. Measurements. Males. BL = 3.24–3.54 mm, BW = 2.32–2.45 mm, HL = 1.09 mm, HW = 1.06 mm, PL = 1.12 mm, PW = 2.23 mm, PA = 100°, EL = 2.53 mm, EA = 130°, AL = 0.91 mm, AW = 0.28 mm.

Females. BL = 3.48–3.74 mm, BW = 2.52– 2.34 mm, HL = 1.20 mm, HW = 1.18 mm, PL = 1.24 mm, PW = 2.42 mm, PA = 100°, EL = 2.75 mm, EA = 130°, SL = 0.41 mm.

Body ( Fig. 2-1A ) short, broadly ovate, almost rectangular; dorsum smooth, mostly yellowish brown. Antennomeres 1-5 yellow, 6-11 brown; labrum and mandibles black. Pronotum with basal margin black. Legs and venter yellowish brown.

Head ( Fig. 2-1D ) nearly round; distinctly and sparsely punctate. Eyes reniform; superior eye-lobes separated by slightly greater distance than antennal insertions. Clypeus finely and transversely wrinkled, anterior margin arcuately emarginated. Antennae ( Fig. 2-1E ) reaching elytral humeri, scape clubbed, pedicel oblong, about half as long as scape, antennomeres 3–5 slender, 3 rd as long as pedicel, 4 th as long as 5 th, 6–11 somewhat broadened and flattened, last pointed apically.

Pronotum ( Fig. 2-1A ) smooth, much broader basely than apically, basal width about twice as long as pronotal length. Anterior margin weakly arched. Posterior margin serrate and undulated, and produced into an obtuse angle of about 100° at middle. Disc evenly convex, impunctate. Posterior margin sinuate with fine serration.

Elytra ( Fig. 2-1A ) oblong, humeri somewhat prominent, widest slightly behind humeri, feebly rounded at sides and apex. Disc sparsely and finely punctate, with 11 regular striae, intervals with scattered minute punctures. Epipleural lobe ( Fig. 2-2A ) moderately large, lateral margins slightly expanded ventrally with rounded lobe at basal 1/3 of elytron, with both lobe sides forming angle of 130°; epipleura obliquely placed and visible in lateral view.

Venter ( Fig. 2-1C ) clothed with short pubescence and punctures. Prosternum ( Fig. 2-2B ) trapezoidal, anterior margin not protruding, posterior margin nearly straight, central ridge absent, lateral ridges elevated. Mesoventrite broad, twice as wide as long. Metaventrite with dense coarse punctures. Pygidium with dense punctures and short pubescence.

Aedeagus. ( Figs. 2-1H–J; 2-2D–F ) Median lobe elongate, about twice as long as wide, nearly parallel-sided. Apex of median lobe slightly narrower than middle, acute at apex, moderately curved in lateral view; each side of apex and the middle region of ventrally-dilated part with long setae; sparsely punctate on ventral side of distal part. Median orifice with median sclerite bending inwards above surface. Inner sac rather broad, lantern-shaped, dilated at middle, posterior margin nearly straight. Tegmen Y-shaped, weakly sclerotized, almost translucent.

Female. Body more robust than male, apical hollow in ventrite 5 deep and round. Spermatheca ( Figs. 2-1F; 2-2C ) falcate, acute-angled bending at apex 2/3, moderately acute at apex, slightly dilated at 1/3 from base, then become narrower; duct weakly sclerotized, irregularly coiled. Rectal sclerites ( Fig. 2-1G ) strongly sclerotized, not connected between two rectangular sclerites on ventral side.

Distribution: China (Henan, Gansu, Sichuan).

Diagnosis. This new species is similar to A. fracticeps , but it can be distinguished from the latter by the smaller body size and paler body surface, the elytral widest just behind humeri, the elytral epipleural lobe forming an angle of 130°, and antennmeres 1-5 yellow but 6-11 brown.

Etymology. The specific epithet is derived from the Chinese name (Pinyin) of the type locality, Daofu.

Figures

FIGURE 2-2. Adiscus daofuensis Duan & Zhou, sp. nov.:A. epipleural lobe of elytra; B. prosternum; C. spermatheca; D. lateral view of aedeagus; E. dorsal view of aedeagus; F. ventral view of aedeagus. (Scale bars: A–B = 0.5 mm, C–F = 0.2 mm).