Cionus nubilosus Rosenschoeld, 1838

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 : 45-48

23. Cionus nubilosus Rosenschoeld ( Figs 23a–f )

Cionus nubilosus Rosenschoeld, 1838: 739 .

Cionus virgatus Rosenschoeld, 1838: 738 (syn. n.).

Cionus decorus Boheman, 1845: 180 (syn. n.).

Type locality. Cape of Good Hope ( South Africa).

Type series. This species was described from specimens collected in “Caput Bonae Spei” received by Chevrolat. At NHMS under the name “nubilosus” we examined one male syntype labelled “21 [printed] / Cionus nubilosus, Schr. 4.739.19, Cbsp / Chevrol., C. b. sp. [underside of a blue card] / Coll. Chevr. / Typus”, which we designated as the lectotype by adding the following label “ LECTOTYPE Cionus nubilosus Rosensch. des. Caldara & Košťál 2014” and two other specimens similar to the lectotype but lacking requisites for considering them as paralectotypes since labelled merely “♁ [blue paper] / Coll. Chevol.” and “ ♀ / Coll. Chevol.” (NHMS).

Synonyms. Cionus virgatus was described on one page before C. nubilosus based on specimens from “Caput Bonae Spei” received by Drège. We examined one specimen labelled “♁ Cap b. sp., Drège / Typus”, which we designated as the lectotype by adding the following label “ LECTOTYPE Cionus virgatus Rosensch. des. Caldara & Košťál 2014”. It differs from the lectotype of C. nubilosus only by the elytral vestiture which lacks spots and is formed only by vittae. We decided to consider this species as a synonym of C. nubilosus and not vice versa since the vestitural pattern of the latter form is the most common one.

Cionus decorus was described based on specimens from Port Natal obtained by J. Wahlberg and preserved according to the original description in Museum Holm ( Sweden). However, at NHRS under the label “decorus” there is a specimen labelled “EZ [Ecklon & Zeyer] / Typus / [big rectangular brown card]” perfectly corresponding to Boheman’s description, where the author writes “ Cionus decorus (Schh.) .....Statura et summa similitudo Cioni virgati, nonnihil minor, ut videtur magis convexus, aliter coloratus. Anne species distincta?”. On the basis of the original description and this specimen, which is morphologically completely identical with the lectotype of C. nubilosus except for the lighter colors of scales of the dorsal vestiture, we consider C. decorus as a synonym of C. nubilosus .

Diagnosis. Pronotum with two pronounced protuberances. Elytral vestiture brown, with whitish maculae and vittae, striae not visible. V 2 in male with distinct tuft of hair-like scales. Claws asymmetrical in male.

Redescription. Male ( Figs 23a–b ). Body: robust, moderately elongated. Head: rostrum stout, short (Rl/Rw 3.35–3.40, Rl/Pl 1.27–1,33), black, in lateral view regularly moderately curved, of same width from base to antennal insertion, then distinctly tapered to apex, in dorsal view parallel-sided, slightly enlarged from antennal insertion to apex; from base to near apex with dense, recumbent, elliptical, moderately short (l/w 3–5), grayish and light brown scales. Head between eyes moderately narrow, half as wide as rostrum at base. Eyes flat. Antennae dark brown, inserted between middle and apical third; scape long (l/w 10); funicle moderately shorter than scape, S1 moderately robust, moderately more robust than and as long as S2, 2.0× as long as wide, S2 2.5 × as long as wide, S3–5 as long as wide; club oblongly oval, moderately shorter than funicle, uniformly pubescent. Pronotum: dark brown, with dense, more or less small, irregularly arranged deep punctures, completely hidden by dense, recumbent, moderately long (l/w 5–7), rectangular, intermixed dark brown and light brown scales with whitish scales forming median vitta in basal half and covering sides; conical, distinctly transverse (Pw/Pl 1.66–1.72), widest at base, with rectilinear sides, with small, shallow regular punctures and two distinct lateral protuberances, weakly convex. Prosternum: anterior margin distinctly emarginated. Scutellar shield: heart-shaped, densely covered with elongated white scales. Elytra: dark brown, short (El/Ew 1.15–1.20), subrectangular, widest in basal half, somewhat wider than pronotum (Ew/Pw 1.52–1.58), humeri distinct, rounded, sides rectilinear in basal half, moderately convex on disc; interstriae. slightly convex, with small, shallow, irregular punctures completely hidden by recumbent, dark brown, light brown and white rectangular scales, latter ones forming numerous quadrate to rectangular white spots on odd interstriae and almost completely covering interstria 4 in apical half and interstria 8; striae with moderately deep punctures, half as wide as interstriae, completely hidden by scales similar to those on interstriae. Venter: mesosternal process weakly convex, not emarginated. Metasternum densely covered with uniformly elongated, rectangular brown (at sides) and white (in middle) scales, without hair-like scales. Abdomen with dense, irregular, moderately deep punctures completely hidden by moderately elongated scales, hair-like in middle, on V2 where forming distinct tuft, and on V5; V1 1.6× as long as V2; V1+2 5.5× as long as V3+4, latter ones 0.9× as long as V5. Legs: femora dark brown, with robust sharp teeth; tibiae dark brown, unci absent; tarsi brown, onychium as long as T1–3 combined; claws asymmetrical, one claw 1/2 as long as other. Penis: Figs 23d–f , its body slightly narrowed from base to apex, with short, blunted tip. Flagellum robust, moderately long, bifurcated at base.

Female. Rostrum very slightly longer (Rl/Rw 3.43–3.48, Rl/Pl 1.36–1,43) ( Fig. 23c ), claws symmetrical, abdomen with all scales similar in shape.

Variability. Length 2.8–3.7 mm. This is one of the most variable species with regard to the pattern of the dorsal vestiture, especially of the elytra. In typical specimens, elytra are mainly covered with brown scales, interstriae 4 and 7–8 covered with more or less predominating white scales and a few spots of white scales on odd interstriae. This is the intermediate pattern whereas the range varies from specimens with many white spots to specimens without spots (as in the lectotype of C. virgatus ). Moreover, darker scales vary from pale brown to dark brown, whereas longitudinal striae of white scales vary in number and width.

Remarks. This species is sometimes difficult to identify because of its variability in the pattern of the dorsal vestiture. It is similar to C. pustulatus , from which it differs by the less distinctly conical pronotum with prominent protuberances, elytra usually widest in basal third, and the presence of vittae formed by white scales on some interstriae. It is similar also to C. terrosus , from which it differs by the longer and thin rostrum and asymmetrical claws in males.

Biological notes. In Eastern Cape (Peddie), larvae were collected feeding on Selago corymbose (det. Brent), whereas adults were found on Selago sp. by the second author and on Tetraselago sp. by E. Colonnelli.

Distribution. This species seems to be common in the whole South Africa. It is also known from Lesotho.

Non-type material examined. SOUTH AFRICA: Mpumalanga: Middelburg, XI.1933 (3, SANC); Springboklaagkte, Middelburg, 13.XI.1962, leg. van Schalkwyk (3, SANC). Gauteng: Johannesburg, 9.XII.1973, leg. Reavel (1, TMSA); Pretoria, Hennopsriver, XII.1950, leg. van Schalkwyk (2, SANC); Tarleton, 1.XII.1969, leg. van Schalkwyk (1, SANC). North West: Rustenburg, XII.1951, leg. Capener (3, SANC); Ventersdorp, 8.II.1969, leg. van Schalkwyk (2, SANC). KwaZulu-Natal: Boston nr. Pietermaritzburg, 1450 m, 29°40’S 30°04’E, 30.XI.2015, leg. Košťál (15, MKCS); same data except 24.XI.2017 (23, MKCS); Butterworth, 26.I.1963, leg. van Schalkwyk (3, SANC); Cedara, V.1949, leg. Munro (1, SANC); Margate, 30.51S 30.22E, 23.IV.1977, leg. Cilliers (1, SANC) Richmond, XII.1964 (1, MRAC); Van Reenen, Drakensberg, XII.1926, leg. Turner (3, BMNH). Free State: Adullam Farm near Clarens, 28°32’S 28°28’E, 20–26.II.1980, leg. van Tonder (1, SANC); Allanridge, 22.XI.1961, leg. van Schalkwyk (3, SANC); Bourville, 25.I.1963, leg. van Schalkwyk (3, SANC); Fauresmith (Blaauwbank), 18.XI.1961, leg. van Schalkwyk (17, SANC); Meyerskop, Bethlehem, 7.XI.1963, leg. van Schalkwyk (2, SANC); Mooivlakte, Bloemfontein, 9.XI.1963, leg. van Schalkwyk (1, SANC); Rouxville (Uitkyk), 29.I.1963, leg. van Schalkwyk (3, SANC); Tussen-die-Riviere Res. nr Bethulie, 20–26.I.1994, leg. Uys (5, SANC); Witkop, Senekal, 6.II.1964, leg. van Schalkwyk (3, SANC). Northern Cape: Kimberley (Smookspan), 15.XI.1961, leg. van Schalkwyk (2, SANC); Namaqualand, Kotzesrus, 30°57’S 17°50’E, 23.VIII.1979, leg Endrödy-Younga (1, TMSA); Nieuwoudtville, 31°23’S 19°06’E, 14.IX.1985, leg Endrödy-Younga (16, TMSA); Olifantshoek E, 24.II.1984 (1, TMSA);Vanrhyn’s Pass, 31°23’S 19°02’E, 24.X.1981, leg Endrödy-Younga (1, TMSA). Eastern Cape: Alexandria Forest, 95 km WSW Alexandria, 22.VIII.1998, leg. du Plessis (1, SANC); R72– 30 km W Alexandria, 33°36’S 26°08’E, 6.XI.2006, leg. Colonnelli (1, ECCR); Algoa Bay, leg. Brauns (2, BMNH); Aliwal North, XII.1922, leg. Turner (3, BMNH); Aliwal North, 8.II.1964, leg. van Schalkwyk (3, SANC); Aliwal North (Nuwe Jaarspruit), 20.XI.1961, leg. van Schalkwyk (1, SANC); Aliwal North, Buffelsvlei, 28.I.1963, leg. van Schalkwyk (5, SANC); Aliwal North, Strydfontein, 28.I.1963, leg. van Schalkwyk (3, SANC); road Atherston to Stonehaven, 33°20’S 26°21’E, 12.XI.2005, leg. Osella (1, GOCV); Bethelsdorp, XI.1952, leg. Munro (1, SANC); vicinity of Coega, 33°47’S 25°36’E, 16.XI.2006, leg Colonnelli (1, ECCR); Fort Beaufort, IX.1952, leg. Munro (1, SANC); Grahamstown, 8.XII.1977, leg Endrődi (1, HNHM); Grahamstown, Manley Flat, VII.1947, leg. Munro (13, SANC); Grahamstown, Faraway Farm, 33°20’S 26°28’E, 22.XI.1988, leg. Grobbelaar (6, SANC); Grahamstown, Botanic Garden, 30.I.1991, on Selago corymbosa (1, BMNH); Grahamtown to Southwell, 13.XI.2006, leg. Colonnelli (1, ECCR); road N2, 10 km SW Grahamstown, 33°22’S 26°28’S, 10–11.XI.2005 (2, ECCR); R343, 10 km SE of Grahamstown, 33°22’S 26°28’E, 3.V.2005, leg. Audisio (1, ECCR); Gqeberha [formerly Port Elizabeth], 13.VIII.1957, leg. Taylor (4, SANC); Hankey, 33°50’S 24°55’E, 26.XI.2015, leg. Košťál (3, MKCS); Jeffreysbaai, 34.02S 28.20E, leg. van Tonder (4, SANC); St. Francis bay, Jeffrey’s bay, 33°57’S 24°57’E, 25.XI.2015, leg. Košťál (1, MKCS); ditto, 29.XI.2018 (3, MKCS); Kareedouw Pass, 33°57’67”S 24°16’15”E, 16.XI.2006, leg. Colonnelli (3, ECCR); Katberg, 14–26.XI.1932, leg. Turner (2, BMNH); Knisna, 34°02’S 23°03’E, I.1979, leg. Van Tonder (1, SANC); Komga, 600 m, 32°34’S 27°56’E, 25.XI.2017, leg. Košťál (7, MKCS); Kruisfontein, Humansdorp, 33°59’S 24°46’E, 27.XI.2015, leg. Košťál (28, MKCS); Kruisfontein, Impofu Dam, 34°02’S 24°34’E, 27.XI.2015, on Selago sp. , leg. Košťál (10, MKCS); Loerie, 33°52’S 25°02’E, 25.XI.2015, leg. Košťál (5, MKCS); Peddie, III.1932, ex larva on Selago corymbosa , leg. Brent (2, BMNH); 5 km E Port St. Johns, 31°36’58”S 29°34’61”E, 8–9.XI.2006, leg. Colonnelli (2, ECCR); Suurberg Pass, 900 m, 28.XI.1988, leg. Grobbelaar (6, SANC); near Thornhill, 33°54’27”S 25°07’03”E, 16.XI.2006, on flowers of Tetraselago (Scrophulariaceae) , leg. Colonnelli (2, ECCR); Uitenhage, 1230 m, 33°58’S 24°02’E, 16.XI.2006, leg. Osella (1, GOCV); Zuurberg Nat. Park, 550 m, 33°21’S 25°44’E, leg. Osella (1, GOCV). Western Cape: Bookram farm, 32°39’S 18°17’E, 30.VIII.1981, leg Endrödy-Younga (1, TMSA); Cape Town, 1937–38 (2, BMNH); Cape Town 65 km N, 33°21’S 18°15’E, 30.VIII.1983, leg Endrödy-Younga (1, TMSA); Cape of Good Hope, Table Mountain (8, BMNH); Cape Town, W slope Table Mountain, 6.XI.1949, leg. Malkin (1, BMNH); Cederberg, Boshof, 32°20’S 18°59’E, 17.IX.1985, leg Endrödy-Younga (6, TMSA); Cederberg Mts.,Matjiesfontaine Reserve, 32°32’23”S 19°19’05”E, 12.XI.2018, leg. Borovec (12, RBCS); Cederberg Mts., SE Uitkyk Pass, road to Driehoek, 32°25’07”S 19°09’09”E, 11.XI.2018, leg. Borovec (5, RBCS); Cederberg Mts., SE Uitkyk Pass, Kliphuis, 32°28’03”S 19°13’01”E, 12.XI.2018, leg. Borovec (19, RBCS; 6, RCCM); Cederberg W.A., Eikeboom trail, 955 m, 32°45’S 19°16’E, 6.XII.2013, leg. Wanat (1, MNHW); Cederberg W.A., 1 km S of Eikeboom, 930 m, 32°46’S 19°17’E, 6.XII.2013, leg. Wanat (1, MNHW); 13 km E. Ceres, 17.XI.2007, leg. Colonnelli (1, ECCR); Doorn River, XI.1931, leg. Ogilvie (1, BMNH); Eshowe, IX.1949, leg. Capener (4, SANC); George, 19–21.I.1922, leg. Turner (2, BMNH); Farm Wiedou, Gifberg, 17.IX.1986, leg. Oberprieler (1, SANC); Farm Wiedou, Gifberg, 17.IX.1986, leg. Oberprieler (1, SANC); Katbakkies Pass, 21.XI.1984, leg. Prinsloo (1, SANC); Keurboomrivier Mond nr. Plettemberg, 13.II.1990, leg. Jonsson (2, SANC); Langebaanweg, 29°57’S 18°08’E, 24.VIII.1983, leg Endrödy-Younga (2, TMSA); Milnerton, I.1926, leg. Turner (2, BMNH); Mossel Bay, IX.1924, leg. Turner (4, BMNH); Oudtshoorn, X.1931, leg. Mackie (1, BMNH); Outeniekwaberge 33°52’S 23°11’E, 14.XII.1977, leg Endrödy-Younga (15, TMSA); Paternoster, 32°81’S 17°86’E, on Scrophulariaceae , 22.IX.2018, leg. Haran (1, CBGP); Plettenbergbaai, 34.03S 23.23E, I.1979, leg. van Tonder (1, SANC); Prince Alfred’s Pass nr. Uniondale, 12.II.1990, leg. Jonsson & Uys (3, SANC); Saasweld nr George, 33.57S 22.35E, 12.II.1985, leg. Breytenbach (1, SANC); Somerset East, X.1930, leg. Turner (8, BMNH); Stellenbosch, 27.XI.1964, leg. Capener (1, SANC); Swellendam, II.1932, leg. Turner (1, BMNH); S. Swellendam, De Hoop N.R., 8.XI.2011, leg. Borovec (8, RBCS); Swellendam, 34°00’S 20°82’E, on Scrophulariaceae , 23.VIII.2018, leg. Haran ( CBGP); Top uan, Bains Kloof, 25.IX.1978, leg. Holm and Scholtz (1, SANC); Velddrif, 32°72’S 18°19’E, 27.VII.2019, on Scrophulariaceae , leg. Haran” (11, CBGP); Villiersdorp, 1.XII.1964, leg. Capener (2, SANC); Wildernis, 3.X.1981, leg. Scholtz (5, SANC). LESOTHO: Hodson’s Peak, 3000 m, 29°37’S 29°17’E, 12.III.1976, leg Endrödy-Younga (5, TMSA); Molomoshoek, III.1944, leg. Munro (2, SANC).

Figures

FIGURES 23–24. FIGURE 23. Cionus nubilosus. 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 24. Cionus histrio. 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.