Afrosmicronyx umbrinus ( Hustache, 1940 )

Haran, Julien & Perrin, Hélène, 2017, Revision of the genus Afrosmicronyx Hustache (Coleoptera, Curculionidae, Curculioninae), Zootaxa 4365 (2), pp. 132-148 : 144-146

Afrosmicronyx umbrinus ( Hustache, 1940)

Figs 2J , 4J , 5J , 6J

Smicronyx (Afrosmicronyx) umbrinus Hustache, 1940: 186

Material examined. Lectotype ♀: ‘ Senegal. Sinthum-Malène. Risbec. viii.1939 ’, ‘ Afrosmicronyx umbrinus . Hust. Hoffmann det.’ (lectotype designated by Anderson & Cox 1997, MNHN, Hoff. coll). Other material. Burkina- Faso, Farako-Bâ , 6.x.1993, J.C. Streito leg. (1 ♀, JHcoll); Bobo-Dioulasso, iv.1957, Hamon leg., ORSTOM Paris (1 ♀, MNHN, Gene. coll). Cameroun, Maroua , v. iii .1977, P. B. de Miré, « mil field », JHAR _00108 (1 ♀, CBGP); Koza , 18.ix.1977, P. B. de Miré, « bush », JHAR_00107 (1 ♂, CBGP). Democratic Republic of the Congo, Lusinga , Mukana, 20.vi.1945, G.F. de Witte. Leg. 149–151, ‘ Paratypus’, ‘ E. Voss det., 1960 Smicronyx armipes n.

sp.’, ‘ Smicronyx sp. 1. not armipes Voss , det. M.L. Cox 1994’ (1 ♀, RMCA). Mauritania, Ouroghada, Ritta, 28.ii.1958, F. Mateu leg., Hoffman det. (1 ♂, MNHN, Hoff.coll). Namibia, Kaoko Otavi, iii.1926, SAM-COL- A 051373 (1 ♀, SAMC). Niger, Tarma, 10.iv.1986, H. Guierremont, «irrigated mil, leaves» (1 ♀, DGPVN). Senegal, Thyes, Auvert leg. (1 ♂, MNHN, Hust.coll); Badi (Niokolo Koba national Park), 15.viii–25ix.1955, mission IFAN (3 ♂, IFAN).

Redescription. (♀) after Anderson & Cox (1997). Body length of examined specimens 3.8–4.0 mm. Colour. Body integument brownish black; vestiture consisting of rounded recumbent scales, as long as wide or slightly elliptical, scales brown with shades of gray on elytra. Head. Rostrum longer than head plus prothorax, thin, moderately downcurved except at base where curvature is more pronounced, densely covered by scales at base, less densely at antennal insertion, smooth at apex, bearing 3 dorsal carinae visible near antennal insertion, transversal furrow at base of rostrum shiny and deep, head short; antennae reddish, segments 1 and 2 elongate, longer than 3, segment 1 longer than 2. Prothorax. Isodiametric, widest just behind middle, greatly narrowed at apex, sides rounded; integument densely and coarsely punctuate; scales brownish-gray, paler along a narrow longitudinal strip, mostly visible near scutellum, vestiture with a mix of broadly ovate scales and arcuate setiform scales. Elytra. Sides moderately convex, sub-parallel in basal half, rounded in apical half, widest near middle (ratio w/l: 0.64); humeri raised, covered with whitish scales; striae narrow, interstriae flat wide and shiny, apex of interstria 5 with moderate declivital callosity, usually with whitish scales, followed by depression; scutellum small but visible, squamose. Abdomen. Underside covered with grayish scales, ventrites 1 and 2 elongate, 1 longer than 2+3, and slightly longer than 3–5. Legs. Dark brownish, femora clavate, armed with one ventral tooth; pro- and mesotibiae straight, fore-tibiae slightly bisinuate, all tibiae armed with one acute ventral tooth in basal third. Genitalia. Penis short (ratio w/l: 0.58), sides sub-parallel, slightly converging near apex, apex rounded, curvature in lateral view greater in apical half ( Fig. 6J ). Females are distinguished from males by their more pointed ventral tooth on tibiae, by their slightly longer, stouter rostrum, which is less coarsely punctate in apical half.

Life history. The larvae develop in fruits of Striga hermonthica and S. gesnerioides ( Anderson & Cox 1997, Traoré et al. 1995). Adults have been collected in February, August and October.

Distribution. This species is widely distributed in West Africa and eastwards through sub-Saharan Africa to Tanzania ( Anderson & Cox 1997). Countries recorded here are Cameroon, Democratic Republic of the Congo, Burkina Faso, Mauritania and Senegal.

Discussion. Afrosmicronyx umbrinus is similar to A. dorsomaculatus , but its elytra do not have whitish stripes along the sides. The general appearance of this species is similar to that of A. mirei and A. madagascariensis (see these species for further distinguishing characters). A male specimen from Namibia (SAMC) examined is similar to typical A. umbrinus but has shorter antennae and a longer penis and may represent a different species. It has been labelled as Afrosmicronyx aff. umbrinus .

Figures

FIGURE 2. Habitus of species of Afrosmicronyx. A. Afrosmicronyx giganteus (Hustache), neotype ♀. B. A. quadrituberculatus (Hustache),lectotype ♂.C.A.sopubiae(Marshall),lectotype ♂.D.A.angolanus (Hustache),holotype ♂.E.A.maerens (Marshall), lectotype ♂. F. A. dorsomaculatus(Cox), specimen from Sudan (♀). G. A. mirei sp.n., holotype ♂. H. A. armipes (Voss), holotype ♂.I. A. madagascariensissp.n., holotype♂. J. A.umbrinus(Hustache) lectotype ♀.Scale bars (A to J): 0.2 mm.

FIGURE 4. Head and prothorax in lateral view of species of Afrosmicronyx. I. A. madagascariensis sp. n., holotype ♂. J. A. umbrinus (Hustache), lectotype ♀.

FIGURE 5. Ventrites of Afrosmicronyx spp.. A. Afrosmicronyx giganteus (Hustache), neotype ♀. B. A. quadrituberculatus (Hustache), lectotype ♂. C. A. sopubiae (Marshall), lectotype ♂. D. A. angolanus (Hustache), holotype ♂. E. A. maerens (Marshall), lectotype ♂. F. A. dorsomaculatus (Cox), specimen from Sudan (♀). G. A. mirei sp. n., holotype ♂. H. A. armipes (Voss), holotype ♂. I. A. madagascariensis sp. n., holotype ♂. J. A. umbrinus (Hustache), lectotype ♀. Scale bar = 1 mm.

FIGURE 6. Penis of Afrosmicronyx species, dorsal (left) and lateral (right) view. A. Afrosmicronyx giganteus (Hustache), specimen from Cameroon. B. A. quadrituberculatus (Hustache), lectotype. C. A. sopubiae (Marshall), lectotype. D. A. angolanus (Hustache), holotype. E. A. maerens (Marshall), lectotype. F. A. dorsomaculatus (Cox), specimen from Mauritania. G. A.mirei sp.n., holotype.H.A.armipes (Voss),holotype.I. A.madagascariensis sp. n., holotype.J.A.umbrinus (Hustache), specimen from Cameroon.Scale bar = 200 µm.