Cionus convexiusculus, Caldara & Košťál, 2023

Caldara, Roberto & Košťál, Michael, 2023, A Taxonomic Revision Of The Afrotropical Species Of The Weevil Genus Cionus (Coleoptera: Curculionidae), Zootaxa 5288 (1), pp. 1-98 : 80

44. Cionus convexiusculus sp. n. ( Figs 44a–f )

Type locality. Mont d’Ambre ( Madagascar) .

Type series. Holotype, male “ Mt. d’Ambre , Madagascar ” ( MNHN) . Paratypes: same data as holotype (1, MNHN) ; “ Madagascar / Samml. K.F. Hartmann Ankauf 1941.1” (2, RCCM; 3, SMTD); “ Madagascar / 1909 17 / A. Mad. ” (1, SMTD) ; “ Madagascar / 1909 17 / Vohémar, A. Mad.” (1, SMTD) ; “ Madagascar, Vohémar / Cionus catenatus Frm. / Samml. K.F. Hartmann Ankauf 1941.1” (1, SMTD) .

Diagnosis. Rostrum stout, short. Head between eyes very narrow. Pronotum distinctly conical, without protuberances. Elytra globose, with subrecumbent, sparse, hair-like, intermixed whitish and dark brown scales, partly forming blurred spots on odd interstriae, striae slightly sinuate, well visible. Claws symmetrical in both sexes.

Description. Male ( Figs 44a–b ). Body: stout, globose. Head: rostrum: stout, short (Rl/Rw 3.10–3.15, Rl/Pl 1.18– 1.22), black, in lateral view regularly moderately curved, with dorsal outline at base moderately concave, tapered from base to apex, in dorsal view distinctly divergent from base to apex, striate-punctate, indistinctly carinate to apex, from base to apex covered with recumbent, sparse, moderately long (l/w 4‒6), brown scales. Head between eyes very narrow, 0.25× as wide as rostrum at base. Eyes flat. Antennae dark brown, inserted between middle and apical 1/3; scape moderately long (l/w 7); funicle distinctly shorter than scape, S1 more robust and shorter than S2, 2.5× as long as wide, S2 4.0 × as long as wide, S3–5 as long as wide; club oblongly oval, shorter than funicle, regularly pubescent. Pronotum: black, without protuberances, with dense and shallow punctures, intervals among punctures shallow, smooth, covered with recumbent, sparse, hair-like (l/w 8–10), dark brown scales; conical, distinctly transverse (Pw/ Pl 1.75–1.80), widest at base, with rectilinear sides, slightly convex on disc. Prosternum: anterior margin distinctly emarginated. Scutellar shield: triangular, densely covered with distinctly long, light brown scales, more elongated than those on elytra. Elytra: black, very short (El/Ew 1.00–1.03), globose, widest at middle, distinctly wider than pronotum (Ew/Pw 1.75–1.80), humeri moderately prominent, rounded, sides moderately rounded, distinctly convex on disc; interstriae feebly visible, slightly sinuate only at base, regularly moderately convex, with dense shallow punctures, clearly visible between recumbent, sparse, hair-like (l/w 8–10), intermixed whitish and dark brown scales partly forming blurred spots on odd interstriae; striae clearly visible, with dense, deep, almost regularly arranged punctures, as wide as interstriae, intervals between punctures moderately narrow. Venter: mesosternal process slightly convex, moderately emarginated. Metasternum with moderately dense, elongated, light brown and whitish scales. Abdomen with dense, moderately regular, moderately deep punctures clearly visible between sparse, hair-like, grayish scales, all similar in shape and length; V1 1.6× longer than V2, V1+2 5.0× longer than V3+4, latter ones 0.7× as long as V5. Legs: covered with moderately dense, elongated light brown and whitish scales; femora black, with stout and sharp teeth; tibiae black, without unci; tarsi dark brown, onychium as long as T1–3 combined; claws symmetrical. Penis: Figs 44d–f , its body very long and very narrow, sides subparallel to apex proximity, apex emarginated. Flagellum not visible.

Female. Rostrum slightly longer (Rl/Rw 3.23–3.26; Rl/Pl 1.26–1.31) ( Fig. 44c ).

Variability. Length 2.6–3.0 mm. We found no noteworthy differences among specimens of the type series.

Etymology. The Latin adjective means “slightly convex” pointing out the weak convexity of the elytral interstriae.

Remarks. This species is similar to C. compactus , from which it differs by shorter and indistinctly raised scales on dorsum, smaller and more regular punctures on elytral striae, symmetrical claws also in male.

Distribution. Northern Madagascar.

Figures

FIGURES 43–44. FIGURE 43. Cionus compactus a: body in dorsal view (male), b: body in lateral view (male), c: rostrum in lateral view (female), d: penis in ventral view, e: penis in lateral view, f: apex of penis in dorsal view. FIGURE 44. Cionus convexiusculus sp. n. a: body in dorsal view (male), b: body in lateral view (male), c: rostrum in lateral view (female), d: penis in ventral view, e: penis in lateral view, f: apex of penis in dorsal view. Not to scale.