Gansuapteris Ruan and Konstantinov, 2017

Ruan, Yong-Ying, Konstantinov, Alexander S., Prathapan, K. D. & Yang, Xing-Ke, 2017, New contributions to the knowledge of Chinese flea beetle fauna (I): Gansuapteris new genus and Primulavorus new genus (Coleoptera: Chrysomelidae: Galerucinae), Zootaxa 4282 (1), pp. 111-122 : 112-114

Gansuapteris Ruan and Konstantinov , new genus

( Figs 1–3 )

Type species. Gansuapteris fulvus Ruan and Konstantinov , new species.

Etymology. This new genus is named after the type locality—Gansu province in China and the absence of hind wings. The name is masculine.

Distribution. China.

Host plant. Unknown.

Description. Body small, ovate in dorsal view, moderately convex in lateral view. Color non-metallic. Dorsum glabrous. Pronotum subquadrate, width slightly exceeds length. Width of pronotum at base nearly equal to that at apex. Width of elytra at base exceeds that of pronotum at base.

Head hypognathous. Vertex glabrous without punctures. Frontal ridge moderately developed, narrow. Either side of frontal ridge with a few white setae. Antennal calli absent. Top of frontal ridge merges with vertex. Width of frontal ridge about as great as that of one antennal socket. Frontal ridge in lateral view moderately convex. Supraorbital and orbital sulci present. Supraantennal sulcus, frontolateral sulcus poorly developed. Supracallinal sulcus absent.

Orbit wide, slightly wider than diameter of antennal socket. Eye small, inner margin nearly straight in frontal view. Distance between eyes (just above antennal sockets) approximately 3 times diameter of one eye in frontal view. Labrum flat, without projections in middle, with 6 setiferous pores, anterior margin slightly concave. Apical maxillary palpomere conical. Supraorbital pore moderately developed. Clypeus band like. Antennal sockets situated nearly at middle level of eye.

Antenna, with 11 antennomeres, hardly reaching middle of elytra over pronotum. First antennomere about as long as next two combined. Distal antennomeres robust, wider than middle ones.

Pronotum glabrous, gently convex, without impressions. Diameter of pronotal punctures 3–4 times smaller than distance between them. Pronotal punctures much smaller than those on elytra. Anterolateral callosity of pronotum morderately developed, truncate, elongate, facing anterolaterally. Sides of pronotum straight, almost parallel to each other. Pronotal base nearly straight, slightly emarginated in middle. Lateral margin of pronotum complete, moderately explanated. Posterolateral setiferous pore of pronotum not protruding laterally beyond lateral margin.

Procoxal cavities open. Intercoxal prosternal process extends a little beyond procoxae, concave along top, lateral margins concave, apex wider than middle with straight posterior end.

Elytral base wider than base of pronotum. Humeral calli and hind wings absent. Elytral punctures coarse, confusedly arranged. Scutellum large, semicircular. Elytral apex rounded, covering entire abdomen. Lateral sides strongly and evenly convex. Epipleura outwardly oblique, gradually narrowing from base to apex, reaching end of elytron, maximum width being less than that of profemur.

Mesosternum more or less flat. Meso- and metasternum without elevated projection in middle. Abdominal ventrites 1 and 2 not fused. Abdominal ventrite 1 much longer than ventrites 2–4 together. Abdominal ventrite 5 about as long as ventrites 4 and 3 together. First abdominal ventrite between coxae without longitudinal ridges. Anterior end of first abdominal ventrite normally wide, truncate.

Pro- and mesotibia without apical spurs. Metatibia with weak, slender apical spur. Metafemoral spring present. Hind and middle tibia without laterally visible excavation distally. Metatibia apparently straight, nearly round in cross-section around its middle. Dorso-lateral side of metatibia with a row of sharp denticles. First metatarsomere articulated at apex of metatibia, slightly shorter than half of metatibia. Tarsomere 3 without incision, slightly longer than wide. Claw simple.

Spermatheca with distinct receptacle, pump and duct. Vaginal palpi resembles that of Chaetocnema Stephens and Longitarsus Latreille , elongate, fused near proximal ¼.

Discussion. Gansuapteris can be differentiated from all Chinese flea beetle genera by the combination of the following characters: (1) absence of antennal calli, (2) elytra without humeral calli and (3) presence of sharp denticles along dorso-lateral margin of hind tibia. Apex of spermathecal pump forming a sclerotized cap with a blunt appendix, absence of incision of third tarsomeres, and the first metatarsomere which is a little shorter than half of metatibia are also noteworthy features.

Figures

FIGURE 1. Gansuapteris fulvus n. sp. (habitus, hand drawing).

FIGURE 2. Gansuapteris fulvus n. sp. A: habitus (Holotype, female). B: prothorax, dorsal view. C: head, frontal view. D: vaginal palpi. E: Spermatheca. F: last visible tergite of female, dorsal view. G: head (hand drawing).

FIGURE 3. Gansuapteris fulvus n. sp. A: lateral view of Holotype. B: epipleuron. C: lateral view of head. D: lateral margin of pronotum. E: Lateral view of hind tibia and tarsi, red arrows indicating claw and serrated denticles on dorsal surface of tibia. F: abdominal ventrites of Holotype (female). G: prosternum.