Cionus perlatus 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 : 16-17

5. Cionus perlatus Faust ( Figs 5a–f )

Cionus (Platylaemus) perlatus Faust, 1885: 93 .

Type locality. Lake Malawi ( Tanzania).

Type series. Faust (1885) described this species on an unspecified number of specimens of SMTD from “Nyassa-See” (currently Lake Malawi or Lake Nyasa) without the designation of a holotype. We examined four male syntypes ( SMTD) labelled “[small quadrate golden paper] / Nyassa S. Kirsch / Coll. J. Faust Ankauf 1900 / TYPE” (2 specimens on the same pin, the upper one here designated as the lectotype by adding the printed red label “ LECTOTYPUS Cionus perlatus Faust, R. Caldara des. 2006”, the other labelled as the paralectotype); “Nyassa S. Kirsch / Coll. J. Faust Ankauf 1900 / Cotypus” (2 specimens on different pins, labelled as paralectotypes).

Diagnosis. Antennal club elongated, slightly longer than funicle. Pronotum without protuberances. Prosternum with moderate emargination. Elytra rectangular, with odd interstriae moderately convex, covered with erect, dense, white and black scales arranged in alternating spots, striae rectilinear and well visible. Claws asymmetrical in male.

Redescription. Male ( Figs 5a–b ). Body: moderately elongated. Head: rostrum stout, short (Rl/Rw 2.82–2.87; Rl/Pl 1.33–1.38), black, in lateral view moderately curved, very slightly tapered from base to apex, in dorsal view with sides slightly enlarged from base to apex, striate-punctate in entire length, in basal 2/3 with subrecumbent, moderately dense, moderately long (l/w 4–7), elliptical, intermixed whitish and light brown scales. Head between eyes moderately narrow, 0.4× as wide as rostrum at base. Eyes flat. Antennae dark brown, inserted at apical 1/3; scape long (l/w 9); funicle short, distinctly shorter than scape, S1 slightly more robust, 1.4× longer than S2, 1.3× as long as wide, S2 as long as wide, S3–5 transverse; club oblongly oval, slightly longer than funicle, regularly pubescent. Pronotum: black; without protuberances, with approximately regular, deep, dense punctures, intervals between punctures shining, almost smooth, moderately visible among recumbent to subrecumbent, moderately dense, moderately long (l/w 5–7), elliptical, intermixed whitish and light brown scales, the light ones forming five irregular more or less distinct vittae; subconical, distinctly transverse (Pw/Pl 1.80–1.83), widest at base, with slightly rounded sides, moderately convex on disc. Prosternum: anterior margin with moderate emargination. Scutellar shield: subcordate, with dense, elongated, white scales. Elytra: black, subrectangular, long (El/Ew 1.44–1.50), moderately wider than pronotum (Ew/Pw 1.39–1.46), humeri moderately prominent, sides subparallel to slightly rounded, somewhat convex on disc; even interstriae flat, covered with moderately deep, small, moderately dense punctures, which are feebly visible between recumbent, moderately dense, whitish and light brown scales, odd interstriae moderately convex, covered with erect, dense, white and black scales arranged in alternating spots; striae moderately visible, straight, 1/3 as wide as interstriae, with partially regular, dense, deep, broad punctures, intervals between punctures narrow, situated at same level as interstriae. Venter: mesosternal process moderately convex, slightly emarginated. Metasternum covered with moderately sparse, elongated whitish and brown intermixed scales. Abdomen with moderately deep, dense punctures feebly visible between sparse, regularly arranged, whitish, long, approximately equally long scales; V1 1.5× longer than V2; V1+2 5.0× longer than V3+4, latter ones 0.6× as long as V5. Legs: covered with moderately sparse, elongated, whitish and brown intermixed scales; femora black with robust sharp teeth, covered with moderately dense, light brown and white intermixed scales; tibiae dark brown, without unci; tarsi brown, onychium slightly longer than S1–3 combined; claws asymmetrical, one claw 1/2 as long as other. Penis: Figs 5d–f , its body elongated, in basal 2/3 with parallel sides, then gradually narrowed, with subacutely pointed tip. Flagellum short, not longer than apodemes, bifurcated at its base.

Female. Rostrum slightly longer (Rl/Rw 2.90–2.94; Rl/Pl 1.36–1.42) ( Fig. 5c ), claws symmetrical.

Variability. Length 3.2–4.3 mm. The numerous specimens examined did not show substantial differences.

Remarks. In the original description, Cionus perlatus was placed in the subgenus Platylaemus Weise, 1883 , a name described at a generic rank, currently synonymous with Cleopus Dejean, 1821 ( Alonso-Zarazaga & Lyal, 1999) and already used by Dixon (1850) for a fossil fish possibly belonging to the family Labridae . This species, which is one of the most widely distributed in the sub-Saharan Africa, however apparently not reaching South Africa, is easily distinguishable from all other Afrotropical species by the moderately elongated subrectangular elytra covered mainly with dark scales and with distinctly contrasted spots of white scales on odd interstriae. Due to the elongated elytra and the lack of pronotal protuberances it seems to be more related to C. pericarti and C. frater than to other species.

Biological notes. The specimens from Ndola ( Zimbabwe) were reared ex pupa from Stereospermum kunthianum Cham. (Bignoniaceae) .

Distribution. West, Central, East and Southern Africa ( Senegal, Burkina Faso, Chad, Nigeria, Kenya, Tanzania, Uganda, Angola, Democratic Republic of Congo, Zimbabwe, Malawi, Mozambique). Not known from South Africa.

Non-type material examined.

SENEGAL: Nioro, 1943, leg. Risbec (1, BMNH). BURKINA FASO: Ouagadougou, VII.1926, leg. Olsufev (3, ZISP). TOGO: Atakpamé (1, ZMHB). NIGERIA: Bantschi to Lokoja, leg. Bucknill (1, BMNH). CHAD: Haut Oubangui, Bessou, a mont de Fort de Possel, IX.1904, leg. Decorse (1, MNHN); NO Fort Archambault, Sara, Goundi, VI.1904, leg. Decorse (3, MNHN). KENYA: Lower Molo, 28.III.1937, leg. Wilkinson (1, BMNH).

TANZANIA: Arusha, 1904, leg. Katona (1, HNHM); Kilimanjaro, south-eastern side, Moschi, 800 m, IV.1912; leg. Alluaud & Jeannel (4, MNHN); Moshi, VII.1905, leg. Katona (1, HNHM); Kilimanjaro, Machame (1, ZMHB); Kilimanjaro, Obstgarten-Steppe, leg. Sjöstedt (1, MNHN); Road to Kilossa, Usagara Distr., 22–26.XII.1910, 1,500 – 2,500 ft., leg. Neave (1, BMNH); Zanzibar, Mhonda-Ouzigoua, I–III.1880, leg. Hacquard (1, MNHN); Zanzibar, Mrogoro, leg. Gommenginger (5, MNHN); UGANDA: Agule, 20.IX.1924, leg. Hargreaves (1, BMNH); Kampala, 15.V.1927, leg. Hancock (7, BMNH); Mount Kadam, Karamoja, IV.1950, leg. van Someren (1, BMNH); Nawanda, 18.X.1952, leg. Magala (3. BMNH). DEMOCRATIC REPUBLIC OF THE CONGO: P.N.U. Kembwile r. g. Kalule North, 28.II.1949 (1, MRAC); Kivu Uvira, leg. Babault (1, MNHN); Lulua, Sandoa, XII.1931, leg. Overlaet (1, MRAC); Nagero, 30.VIII.1952, leg. De Saeger (2, MRAC); Sankuru, M’Pemba (Gandajika), 13.XI.1958, leg. Maréchal (2, MRAC). ANGOLA: M’Pala, leg. Guillemé (3, MNHN). ZIMBABWE: Harare [formerly Salisbury], 15.III.1977 (2, RCCM; 4, SANC); Ndola, II.1953, ex pupa on Stereospermum kunthianum , leg. Cottrell (2, BMNH); Mazoe, 18.I.1929, leg. Hall (1, BMNH); Mwengwa, 13.XII.1913, leg. Dollman (2, BMNH); Ndola, II.1953, ex pupa on Stereospermum kunthianum , leg. Cottrell (2, BMNH). MALAWI: SW of Lake Chilwa, 9.I.1914, leg. Neave (2, BMNH); Chiromo, Ruo river, III.1916, leg. Wood (1, BMNH); Maiwale, 17.I.1932, leg. Lamborn (1, BMNH); between Ft. Mangoche and Chikala Boma, about 4,000 ft, 20–25.III.1910, leg. Neave (1, BMNH); Mlanje, 27.I.1913, leg. Neave (6, BMNH; 2, MKCS; 2, RCCM); Side of Mt. Mlanje, 3,000 –4,000 ft., 3.XII.1913, leg. Neave (3, BMNH); Mlanji Boma, 2,400 ft., 26–30.IV. 3–5.V.1910, leg. Neave (3, BMNH); 2 km E Ndunde, 800 m, 4.XII.1983, legg. Bellamy, Holm, vd Berg, Edwardes (4, SANC); Ruo valley, 2,000 ft., 14.XII.1913, leg. Neave (1, BMNH).

Figures

FIGURES 5–6. FIGURE 5. Cionus perlatus. 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 6. Cionus vicarius. 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.