Cionus distinctus Desbrochers des Loges, 1869

Košťál, Michael & Caldara, Roberto, 2019, Revision of Palaearctic species of the genus Cionus Clairville (Coleoptera: Curculionidae: Cionini), Zootaxa 4631 (1), pp. 1-144 : 87-89

52. Cionus distinctus Desbrochers des Loges, 1869

Figs 52 a–f.

Cionus distinctus Desbrochers des Loges, 1869: 30 . Reitter, 1904: 56. Wingelmüller, 1914: 193; 1921: 105; 1937: 173. Hustache, 1932: 341. A. Hoffmann, 1958: 1219. Caldara, 2013: 123. Alonso-Zarazaga et al., 2017: 185.

Type locality. Corse .

Type series. In coll. Desbrochers ( MNHN), there are five specimens on cards, one male on a single pin and apparently two couples, each couple on another single pin. The male is labeled “ distinctus Desbroch. Corse [Desbrochers´ handwriting] / Ex Musaeo Desbrochers 1914 / MUSÉUM PARIS COLL. DESBROCHERS”. Two couples bear the same last two labels and the following upper labels: “ Corsica / distinctus Db. ” and “distinctus Corse m.”. We remounted and dissected the genitalia of the first, 2.90 mm long male and designated it as the lectotype by adding the label “ LECTOTYPUS Cionus distinctus Desbrochers Michael Košťál des. 2014 [printed red label]”. The remaining four specimens were labeled as paralectotypes accordingly .

Synonyms. None.

Redescription. Male. Body moderately stout, subrotund. Head: rostrum moderately slender, medium long (l/ w 4.2, Rl/Pl 1.22), black to dark brown; in lateral view slightly curved, of same length from base to antennal insertion, then upper outline abruptly curved forming moderate tapering in apical part; in dorsal view of same width from base to apex, in basal part round in cross-section, in apical part dorsoventrally flattened; in basal part very densely longitudinally punctured, in apical part towards apex punctures gradually more sparse and isolated, at apex with median longitudinal smooth shiny area; proximal half of basal part with up- and backwardly oriented, recumbent, intermixed gingery and whitish scales, distal half of basal part with recumbent, thin, grayish hairs, apical part with subrecumbent, forwardly oriented whitish short seta-like scales. Head between eyes narrow, of 0.4 rostrum width at base. Eyes very large, broadly rounded, very slightly protruding from head outline. Antennae brown to reddishbrown, inserted shortly beyond 0.6 of rostrum length; funicle of 0.7 scape length, segment 1 moderately wider than segment 2, segment 1 almost twice, segment 2 twice as long as wide, segments 3–5 as long as wide; club spindle-shaped, about 2.2 × as long as wide, of less than 0.9 funicle length, completely covered with recumbent, light brown hairs and erect, sparse, short whitish sensilla. Pronotum: brown, somewhat wider than long (Pl/Pw 0.66), very densely evenly punctured, punctures of unequal size, some relatively large, subrotund, spaces between punctures much smaller than puncture diameter; covered with unevenly distributed, on sides very densely arranged, in longitudinal broad middle area sparsely distributed, medially and forwardly oriented recumbent to subrecumbent elongate (l/w 3–5) gingery and whitish intermixed scales; widest at base, in basal half slightly, in anterior half more apparently narrowed to anterior margin, with broad shallow constriction before anterior margin, in lateral view in basal half almost flat, then gradually moderately falling to anterior margin. Prosternum: anterior margin with shallow, semicircular, not bounded emargination, separated from coxae by very narrow strip of prosternum. Scutellum: triangular with blunt apex, covered with scales similar to those on elytra, densely punctured. Elytra: reddish-brown, in basal half moderately, in apical half distinctly rounded, short (El/Ew 1.13), widest at 0.4 of their length, at base moderately wider than pronotum (Ew/Pw 1.54), humeri subrotund, slightly prominent, with very shallow posthumeral impression; moderately convex on disc; interstria 1 from 1/4 to 1/2 of medial length very strongly broadened and in preapical area moderately broadened, interstria 2 in dorsal area narrowed to invisible, and considerably constricted laterally, in preapical area in much less extent narrowed and constricted laterally, interstria 3 in dorsal area narrowed and moderately constricted laterally, in preapical area straight encompassing very large transversally elongate dorsal and smaller preapical longitudinally elongate black tomentous maculae with narrow border of mostly gingery scales; interstriae except perimacular areas of approximately equal width, in basal part moderately vaulted; odd interstriae, especially in apical half, with very unevenly distributed, small light patches of whitish and gingery scales, darker patches very sparse, indistinct, gingery and whitish scales densely clustered in lateral subhumeral area forming diffuse irregular orange-looking splash; striae shallow, formed by single rows of evenly densely distributed large punctures; entire surface covered with thin, elongate (l/w 5–8) whitish and broad (l/w 4–6) gingery scales concealing majority of integument. Venter: covered with backwardly oriented, recumbent, whitish hair-like scales, mes- and metepisternum, and lateral part of metasternum covered with densely arranged gingery and whitish scales; mesosternal process flat, transverse, with recumbent hair-like scales, straight at posterior margin, punctured; metasternum flat, transversally punctured to ribbed; ventrites 1 and 2 with shallow broad impression with dense large punctures; ventrite 1 twice as long as ventrite 2, ventrites 1–2 combined 4.5 × as long as ventrites 3–4 combined, ventrites 3–4 combined of 0.8 length of ventrite 5. Legs: reddish-brown, profemora with small teeth, meso- and metafemora with large triangular sharp teeth; femora and tibiae covered with subrecumbent to recumbent gingery and whitish intermixed elongate scales not forming distinct transverse bands, tarsi except onychia with subrecumbent whitish seta-like scales, onychia with recumbent long hairs; protarsal onychia shorter than tarsomeres 1–3 combined, protarsal tarsomere 3 wider than long; protarsal lateral and meso- and metatarsal medial claws moderately shorter than their pair-claws. Penis: Figs 52 d–f, its body medium long, with subparallel, moderately concave sides, bluntly tapered at apex.

Female. Rostrum slightly longer (Rl/Pl 1.31), almost bare in basal part, antennae inserted closer to mid-length of rostrum. Ventrites 1 and 2 without impression, moderately convex. Claws equally long.

Variability. Length ♂♂ 2.61–3.26 mm, ♀♀ 2.89–3.40 mm. This species does not show a significant variabil- ity.

Diagnosis. Cionus distinctus is easily distinguishable by small size, concealed considerable part of elytral integument, very large transverse dorsal black tomentous elytral macula with gingery border, short onychia also in males, and penis shape.

Comparative notes. Cionus distinctus is most closely related to C. schoenherri , from which it differs by considerably smaller body size, transverse dorsal elytral macula, sparsely scaled broad medial longitudinal area from pronotal base to anterior margin, and penis shape.

Biological notes. Hoffmann (1958) reported this species from Scrophularia ramosissima Loisel. and S. umbrosa Dumort. (as S. aquatica ). The specimens were collected from early April to mid July.

Distribution. Corse.

Non-type specimens examined. We examined 66 specimens from various localities in Corse (Ajaccio, Albertacce, Bocognano, Calacuzza, Evisa).

Figures

FIGURES 51–52. FIGURE 51. Cionus schoenherri. 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. FIGURE 52. Cionus distinctus. 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.