Mecinus alternans Kirsch, 1870

Caldara, Roberto & Fogato, Valter, 2013, Systematics of the weevil genus <i> Mecinus </ i> Germar, 1821 (Coleoptera: Curculionidae). I. Taxonomic treatment of the species, Zootaxa 3654 (1), pp. 1-105 : 44-45

23. Mecinus alternans Kirsch

Figs 21 , 124

Mecinus alternans Kirsch, 1870: 173 . Reitter, 1907: 14. Escalera, 1914: 470.

Gymnetron logesi Pic, 1900: 80 . Reitter, 1907: 14.

Type locality. Granada (Andalusía, Spain).

Type series. We have not examined syntypes of M. alterans . However the original description is sufficient to establish that this species really is that usually identified with this name by authors.

Synonyms. Gymnetron logesi was described from specimens collected by Pic at Feriana ( Tunisia). We examined one male specimen from this series (Pic's collection, MNHN) labelled “Feriana / 46 / G. n. sp. non mixtum XX [sic] / type / Logesi Pic ” (lectotype here designated). Reitter (1907) considered M. logesi as synonymous with M. alternans , but did not report whether this was based on the type specimens or the original description alone. Actually the lectotype of M. logesi differs from M. alternans by the elytra being distinctly shorter (El/Ew 1.35 vs. 1.42–1.50) and more convex. It is noteworthy that we examined a specimen with long elytra (as in those usually seen in M. alternans ) collected at Feriana, the type locality of M. logesi , whereas two specimens collected at Daya, and identified as Gymnetron mixtum by Hoffmann (1958), differ distinctly in the elytral length since one has the elytra as in the lectotype of M. logesi and the other as usually found in M. alternans . Therefore we agree with Reitter's opinion and consider the lectotype of M. logesi as a specimen to be placed within the range of variability of M. alternans .

Redescription. Male. Length 2.9 mm. Body: long, subcylindrical, moderately stout ( Fig. 21 ). Rostrum: black with reddish apex, moderately long (Rl/Pl 0.86); in lateral view subcylindrical, weakly curved, weakly narrowed in apical third (as in M. circulatus , fig. 71); in dorsal view with subparallel sides, with hardly visible scrobes, distinctly striate-punctured to near apex, in basal half with recumbent to erect, dense, white and brown, moderately long to long (l/w 5–10), seta-like scales. Head: frons as wide as rostrum at base, without fovea; eyes weakly convex. Antennae: inserted just in front of middle of rostrum; scape moderately long, 4.5x longer than wide; funicle about as long as scape, segment 1 2.5x longer than wide, stouter and twice as long as segment 2, which is as long as wide, segments 3–5 transverse; club short, oval, segment 1 almost glabrous. Pronotum: black except basal third and sides which are reddish, with dense and regular punctures, intervals between punctures smooth and shining, moderately visible between recumbent to erect, somewhat dense, white (forming an almost indistinct narrow vitta along midline) and brown, moderately long to very long (l/w 5–15), seta-like scales; moderately transverse (Pw/Pl 1.32), with moderately rounded sides, with weakly prominent apical constriction, widest between basal third and median third, moderately convex. Elytra: with odd interstriae black and even interstriae reddish; moderately long (El/Ew 1.48), suboval, at base moderately concave, slightly wider than pronotum (Ew/Pw 1.23), with weakly rounded sides, widest at middle, moderately convex on disc; interstriae hardly visible between recumbent to erect, dense, whitish (adpressed at humeri, apex of interstria 1 and 5) and brown, very long (in part longer than width of interstria; l/w 10–20), seta-like scales; striae moderately visible, one third narrower than interstriae, with a row of scales about as long as shorter ones covering interstriae. Legs: stout, with subrecumbent to erect, somewhat dense, whitish and light brown, seta-like scales, in part longer than width of tibia; femora black and reddish, subclavate, unarmed; tibiae reddish, short; protibiae with apical part of ventral surface weakly directed outward; unci dark brown, stout, all equal in length; tarsi reddish, tarsomere 1 1.3x longer than wide, tarsomere 2 about as long as wide, tarsomere 3 bilobed and distinctly wider than tarsomere 2, onychium about as long as tarsomeres 1–3 taken together; claws dark brown, equal in length, fused in basal half. Venter: metasternum moderately convex, clearly visible between recumbent to suberect, sparse, whitish, long, seta-like scales; mesothoracic epimera and meso- and metathoracic episterna with sparse, whitish, long seta-like and wide fringed scales; abdomen with blackish brown ventrites 1–2 and reddish ventrites, with dense, somewhat regular punctures, which are moderately visible between recumbent to subrecumbent, somewhat dense, whitish, very long, seta-like scales; ventrites length ratio 1–2/3–4 1.79. Penis: fig. 124.

Female. As in male except rostrum longer (Rl/Pl 1.04), in lateral view weakly narrowed from base to antennal insertion then cylindrical, antennae inserted at middle of rostrum. Sternite 8: as in M. pascuorum ( Fig. 144 ). Spermatheca: as in M. caucasicus ( Fig. 158 ).

Variability. Length 2.4–3.1 mm. The pronotum varies in width (Pw/Pl 1.28–1.45) and the curvature of its sides. The elytra, which are distinctly variable in length (El/Ew 1.35–1.50) and convexity (see discussion of synonyms), are sometimes mainly covered with white scales and sometimes with brown scales.

Remarks and comparative notes. This species is easily distinguishable from others by the colour of the elytral integument (odd interstriae black, even interstriae reddish) together with the elongate-oval elytra that are distinctly wider than the pronotum. Overall it is somewhat similar to M. elongatus , which differs distinctly by the very elongate and straight rostrum especially in the female (Rl/Pl> 1.30), and the dorsal vestiture formed by more recumbent and sparser scales.

Biological notes. No data are available.

Distribution. Central and southern Spain, Morocco, Algeria, Tunisia.

Non-type specimens examined. SPAIN: Andalucía, Córdoba, El Lomo Logue, 16.IX.1990, Baena leg. (1, AZCM) ; Andalucía, Granada, Rio Darro , 10–25.IV.2004, Anishchenko leg. (1, ZISP) ; Andalucía, Malága, Rio Mar, Torre Molinas , 18.VI.1984, Soler leg. (1, MCNM) ; Aragona, Huesca, Benabarre , 800 m, Borovec leg. (1, RBCS) ; Aragona, Sierra de Loarre , S Jaca, 13.V.1999, Białooki leg. (1, PBCS) ; Castilla-La Mancha, Molinicos , 20.V.1958 (1, MCNM) ; Cataluña, Camarasa, Sierra Carbon , 22.V.2001, Orosz leg. (1, APCB) ; Cataluña, Barcelona , 21.V.1924, Liebmann leg. (1, DEIM) ; Cataluña, Gerona, Figueras , 2.V.2003, Kresl leg. (1, RBCS) ; Cataluña, Gerona, La Escala, 19.VII.1974, Heiss leg. (6, DEIM) ; Cataluña, San Carles de la Rapita, VIII.1934, Museu leg. (1, MNHN) ; Comunidad Valenciana, Alicante , 13.V.1968, Richter leg. (1, OVCK) ; Comunidad Valenciana, Valencia (3, HNHM) ; Comunidad Valenciana, Valencia, Bétera, Moroder leg. (1, MCNM) ; Comunidad Valenciana, Valencia, Burjaset, Moroder leg. (1, MCNM) ; Comunidad Valenciana, Valencia, Torrente, Moroder leg. (1, MNHN) ; Madrid, El Pardo (1, MCNM) ; Madrid, Herrera (Manzanares), Ciudad-Real , VI.1909 (1, MCNM) ; Madrid, Vicâlvaro (1, MCNM) . MOROCCO: Cobo de Agua, Melilla , XI.1908, Arias leg. (1, MCNM) . ALGERIA: Daya (2, MNHN) ; Dra el Mizan, Ancey leg. (1, HNHM) ; Feriana , 4.II.1901 (1, MNHN) ; Oran, Lepitre leg. (4, MNHN) . TUNISIA: Ile de Jerba , 13.V.1996, Bellò leg. (1, GOCA) ; road Le Kef-Sakiet km 18, 18.IV.1993, Zoia leg. (1, GOCA) .

Figures

FIGURES 19–27. Habitus of (19) Mecinus henrici; (20) M. elongatus; (21) M. alternans; (22) M. tanaiticus; (23) M. reichei; (24) M. humeralis; (25) M. circulatus; (26) M. suturalis; (27) M. pyraster. Not to the same scale.

FIGURES 121–132. Penis in dorsal and lateral view of (121) Mecinus desertorum; (122) M. marina; (123) M. henrici; (124) M. alternans; (125) M. reichei; (126) M. tanaiticus; (127) M. circulatus; (128) M. humeralis; (129) M. pyraster; (130) M. comosus; (131) M. simus; (132) M. pirazzolii. Scale bar = 0.2 mm.

FIGURES 144–156. Sternite 8 of (144) Mecinus pascuorum; (145) M. caucasicus; (146) M. marina; (147) M. reichei; (148) M. humeralis; (149) M. circulatus; (150) M. pyraster; (151) M. simus; (152) M. collaris; (153) M. janthinus; (154) M. lixoides; (155) M. sicardi; (156) M. heydenii. Scale bar = 0.2 mm.

FIGURES 157–171. Spermatheca of (157) Mecinus pascuorum; (158) M. caucasicus; (159) M. haemorrhoidalis; (160) M. labilis; (161) M. marina; (162) M. elongatus; (163) M. reichei; (164) M. circulatus; (165) M. pyraster; (166) M. simus; (167) M. comosus; (168) M. lixoides; (169) M. janthinus; (170) M. heydenii; (171) M. collaris. Scale bar = 0.2 mm.