Cionus usambicus Faust

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 : 54-56

28. Cionus usambicus Faust ( Figs 28a–b )

Cionus usambicus Faust, 1899: 331 .

Type locality. Kwai ( Tanzania).

Type series. This species was described based on a single specimen (according to Faust a male, but actually a female), from Kwai (currently in Tanzania), which we examined. It is labelled “[small quadrate golden paper] / Kwai, Weise / usambicus Fst. / Coll. J. Faust Ankauf 1900 / Type ” ( SMTD).

Diagnosis. Pronotum with four moderately pronounced protuberances. Elytra short, with prominent humeri, covered with uniformly light brown scales, interstria 3 more convex at base, striae not visible.

Redescription. Female (holotype) ( Figs 28a–b ). Body: short, globose (length 3.1 mm). Head: rostrum stout, moderately long (Rl/Rw 4.80, Rl/Pl 1.50), blackish; in lateral view regularly moderately curved, of same width from base to apex, in dorsal view parallel-sided to antennal insertion, then slightly widened to apex, distinctly striate-punctate from base to apex, covered with moderately dense, subrecumbent to recumbent, elongated (l/w 5–7), grayish and light brown scales. Head between eyes concave, moderately narrow, 0.6× as wide as rostrum at base, with dense, elliptical grayish scales forming comb around apex of eyes. Eyes flat. Antennae reddish with slightly darker club, inserted between middle and apical third; scape long (l/w 8); funicle moderately shorter than scape, S1 more robust than and as long as S2, 1.7× as long as wide, S2 twice as long as wide, S3–5 as long as wide; club oblongly oval, shorter than funicle, pubescent. Pronotum: reddish, with somewhat irregular, very small, indistinct, very shallow punctures, completely hidden by recumbent, dense, partly imbricate, variously oriented, moderately elongated (l/w 5–8), subelliptical, mostly whitish scales, which are brown in middle of basal half; conical, distinctly transverse (Pw/Pl 1.50), widest at base, with rectilinear sides, weakly convex on disc, with four transversely arranged protuberances each emphasized by tufts of erect whitish and light brown scales. Prosternum: anterior margin distinctly emarginated. Scutellar shield: heart shaped, densely covered with grayish and light brown scales. Elytra: reddish, globose, short (El/Ew 1.13), widest at middle, distinctly wider than pronotum (Ew/ Pw 1.87), humeri distinctly prominent, weakly rounded, sides subparallel, somewhat convex on disc; interstriae flat, almost straight except interstria 3 sinuate, more convex at base, with slightly irregular, very small, indistinct, very shallow punctures, completely hidden by recumbent (only a few weakly raised), dense, imbricate, variously oriented light brown scales, base of interstria 3 with two maculae of dark brown scales, without spots; striae not visible, with moderately deep punctures, 1/3 as wide as interstriae, intervals between punctures situated at same level as interstriae. Venter: mesosternal process moderately convex, slightly emarginated. Metasternum 0.7 × as long as V1. Abdomen with somewhat irregular, very small, indistinct, very shallow punctures, feebly visible between elongated, whitish scales being elliptical at sides and longer, hair-like in middle; V1 1.8× as long as V2; V1+2 4.4× as long as V3+4, latter ones as long as V5. Legs: reddish, integument feebly visible between moderately dense, elongated grayish and light brown scales; femora with robust sharp teeth; tibiae without unci; tarsi with onychium as long as T1–3 combined; claws almost equally long.

Male. Unknown

Variability. We examined only the holotype.

Remarks. This species (at least the female) is similar to almost unicolorous specimens of C. ingratus , from which it differs by the distinctly longer and arcuate rostrum, and by tarsomeres, especially the onychium distinctly longer.

Biological notes. No data are available.

Distribution. Tanzania.

Figures

FIGURES 27–28. FIGURE 27. Cionus terrosus 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. FIGURE 28. Cionus usambicus. a: body in dorsal view (female), b: body in lateral view (female). Not to scale.