Cionus planus, 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 : 80-82

45. Cionus planus sp. n. ( Figs 45a–b )

Type locality. Madagascar .

Type series. Holotype, female “Museum Paris, Madagascar, Coll. Guerin-Méneville 1871 / Madag. / Cionus n.s.” ( MNHN) . Paratype: “ Museum Paris , Madagascar, Goudot 1834 / 4177, 94” (1 female, MNHN) .

Diagnosis. Head between eyes very narrow. Pronotum conical, without protuberances. Elytra subquadrate, interstriae completely flattened, striae slightly sinuate, formed by well visible small punctures.

Description. Female ( Figs 45a–b ). Body: stout, globose (length 3.2 mm). Head: rostrum stout, short (Rl/Rw 3.10–3.14; Rl/Pl 1.14–1.19), black, in lateral view regularly moderately curved, with dorsal outline at base moderately concave, slightly tapered from base to apex; in dorsal view parallel-sided from base to apex, with dense shallow punctures, intervals between punctures flat, smooth, in basal 2/3 covered with recumbent, sparse, moderately long (l/w 4–6), light brown and whitish scales. Head between eyes narrow, 0.25× as wide as rostrum at base. Eyes flat. Antennae dark brown, inserted between middle and apical 1/3; scape long (l/w 9); funicle distinctly shorter than scape, S1 slightly more robust and as long as S2, 2.0× as long as wide, S2 2.2 × as long as wide, S3–5 transverse; club oblongly oval, slightly shorter than funicle, regularly pubescent. Pronotum: black, without protuberances, with dense shallow punctures, intervals between punctures flat, finely rugulose, with recumbent, sparse, hair-like (l/w 8–10), intermixed light brown and whitish scales; conical, distinctly transverse (Pw/Pl 1.73–1.78), widest at base, with rectilinear sides, weakly convex on disc. Prosternum: anterior margin distinctly emarginated. Scutellar shield: subtriangular, covered with brown scales similar in shape and color to those in periscutellar area. Elytra: black, very short (El/Ew 1.02–1.07), globose, widest at middle, distinctly wider than pronotum (Ew/Pw 1.73–1.76), humeri moderately prominent, rounded, sides moderately rounded, distinctly convex on disc; interstriae moderately sinuate at base, flat, with dense shallow punctures, intervals between punctures flat, finely rugulose, feebly visible between recumbent, moderately dense, hair-like (l/w 8–10), intermixed whitish and brown scales, former ones forming spots on odd interstriae; striae clearly visible, with dense, deep, almost regularly arranged punctures, 1/3 as wide as interstriae, intervals between punctures moderately narrow, situated at same level as interstriae. Venter: mesosternal process slightly convex, moderately emarginated. Metasternum with moderately dense, elongated brown scales. Abdomen with dense, moderately regular, moderately deep punctures, clearly visible between sparse, hair-like, whitish scales, all similar in shape and length; V1 1.5× longer than V2, V1+2 5.2× longer than V3+4, latter ones 0.6× as long as V5. Legs: covered with sparse, distinctly elongated, brown scales; femora black, with stout sharp teeth; tibiae black, without unci; tarsi dark brown, onychium as long as T1–3 combined; claws almost symmetrical.

Male. Unknown.

Variability. There are no relevant differences between the two specimens of the type series.

Etymology. The Latin adjective, which means “flat”, refers to completely flattened elytral interstriae.

Remarks. This species is similar in its habitus to C. convexiusculus and C. compactus , from which it distinctly differs by the elytral sculpture having flattened interstriae, and small and more regular punctures of the striae.

Biological notes. No data are available.

Distribution. Madagascar.

Figures

FIGURES 45–46. FIGURE 45. Cionus planus sp. n. a: body in dorsal view (female), b: body in lateral view (female). FIGURE 46. Cionus guttula sp. n. a: body in dorsal view (male), b: body in lateral view (male), c: penis in ventral view, d: penis in lateral view, e: apex of penis in dorsal view. Not to scale.