Mecinus longulus (Desbrochers des Loges)

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 : 27-28

11. Mecinus longulus (Desbrochers des Loges)

Figs 10 , 53 , 116

Gymnetron longulum Desbrochers des Loges, 1893: 42 . Reitter, 1907: 15, 33.

Mecinus longulus (Desbrochers des Loges) . Caldara, 2001: 183.

Gymnetron nigronotatum Pic, 1906: 27 . Reitter, 1907: 23 (syn. n.).

Gymnetron nigronotatum var. vaulogeri Pic, 1930: 14 (syn. n.).

Type locality. Constantine ( Algeria).

Type series. This species was described from male specimens. We examined one of them (MNHN) labelled “ Constantine / longulum” (lectotype here designated).

Synonyms. Pic described M. nigronotatus from specimens that he collected at Mekalia ( Algeria). In Pic's collection (MNHN) we found four syntypes labelled respectively “Mekalia, 31 mai / Gymnetron nigronotatum Pic / type / TYPE” (one male and one female on the same pin; male here designated as lectotype and female as paralectotype); “Mekalia, 31 mai” (one female; paralectotype); “Alg.: Mekalia, 31 mai 1905 / Algérie / nigronotatum nouv. / subrubicundum Rttr. [handwritten by Reitter]” (one female, paralectotype). The lectotype of M. nigronotatus differs from that of M. longulus only by the elytra being slightly shorter and with integument similarly reddish, but slightly darker on interstria 1 and on the median third of interstriae 4 and 5. Therefore we have concluded that the two taxa are synonymous.

Pic described the variety vaulogeri of M. nigronotatus from specimens collected at Chellala ( Algeria). We examined one male of this labelled “Chellala / subrubicundum var.? deflor. [handwritten by Reitter] / v. Vaulogeri Pic” (lectotype here designated). The lectotype of the taxon vaulogeri does not show differences from the lectotype of M. longulus .

Redescription. Male. Length mm 1.7. Body: moderately long, oval, moderately stout ( Fig. 10 ). Rostrum: reddish brown, moderately short (Rl/Pl 0.70); in lateral view weakly concave in basal third then weakly curved, same in width from base to apex; in dorsal view with subparallel sides, with hardly visible scrobes, moderately striate-punctured in basal two thirds, in basal half with recumbent to suberect, moderately dense, white, long (l/w 6–8), seta-like scales. Head: frons wide as rostrum at base, with small fovea; eyes nearly flat. Antennae: reddish with brown club, inserted at middle of rostrum; scape moderately short, 3.5x longer than wide; funicle slightly longer than scape, with segment 1 2x longer than wide, stouter and 1.2x longer than segment 2, which is 1.5x longer than wide, segments 3 and 4 about as long as wide, segment 5 moderately transverse; club moderately long, oval, with segment 1 almost glabrous. Pronotum: reddish except apical constriction and a few small spots on disc, which are dark brown, irregularly and densely punctured, with punctures variable in width, intervals between punctures narrower than bigger punctures, smooth, very shining, clearly visible between subrecumbent to erect, whitish, long to very long (l/w 8–12), seta-like scales; moderately transverse (Pw/Pl 1.31), with moderately rounded sides, with moderately prominent apical constriction, widest in basal third, moderately convex. Elytra: reddish except interstria 1 in basal two thirds, interstria 2 and 3 at apex, interstriae 4–6 and 9 and 10 at middle, which are blackish brown ('anchor-like' pattern), moderately short (El/Ew 1.28), suboval, at base moderately concave, slightly wider than pronotum (Ew/Pw 1.16), with weakly rounded sides, widest at middle, moderately convex on disc; interstriae clearly visible between recumbent to suberect, sparse, whitish and brown, long to very long (0.7–1.5x as long as width of interstria, with longer scales at apex; l/w 8–15), seta-like scales, which are arranged in a single row (partly in two series at apex); striae clearly visible, one third narrower than interstriae, with a row of scales similar in length to shorter ones covering interstriae but slightly thinner. Legs: moderately slender, with subrecumbent to erect, somewhat dense, whitish, seta-like scales, which are slightly shorter than width of tibia; femora reddish, with very small tooth; tibiae reddish, moderately slender, protibiae with apical part of ventral surface weakly directed outward; unci blackish, stout; tarsi reddish, tarsomere 1 1.5x longer than wide, tarsomere 2 weakly transverse, tarsomere 3 bilobed and slightly wider than tarsomere 2, onychium slightly shorter than tarsomeres 1–3 taken together; claws reddish brown, equal in length, fused in basal half. Venter: metasternum brown, moderately visible between somewhat dense, whitish, long, seta-like scales; mesothoracic epimera and meso- and metathoracic episterna with sparse, whitish, long, seta-like scales and wide, fringed scales; abdomen brownish, with sparse and shallow punctures, which are clearly visible between recumbent, sparse, whitish, long, seta-like scales; ventrites length ratio 1–2/3–4 1.79. Penis: fig. 116.

Female. As in male except rostrum longer (Rl/Pl 0.88) ( Fig. 53 ), antennae inserted just before middle of rostrum. Sternite 8 and spermatheca: as in M. pascuorum ( Figs 144 and 157 ).

Variability. Length 1.6–1.8 mm. Sometimes the rostrum is reddish to near base or only in the apical third and in female varies somewhat in curvature. The elytra, as well as the venter, may be completely reddish.

Remarks and comparative notes. This species is usually easily separated from others by the colour of the integument of both pronotum (reddish with apical constriction and some small patches on disc dark brown) and elytra (reddish with a dark brown anchor-like pattern), and by the shape of the rostrum that, in lateral view, is weakly concave in its basal third. The specimens with completely reddish dorsal integument are more difficult to separate from M. tychioides . However the latter species has elytra more flattened on disc and the dorsal margin of the rostrum, in lateral view, is regularly curved from the base and not weakly concave, the body of the penis is truncated at apex and is not convex. It differs from M. sanctus by the pronotum, usually reddish with the apical constriction and some small patches on disc dark brown; the elytra are reddish, usually with a dark brown anchorlike pattern, the rostrum, in lateral view, is weakly concave in its basal third.

Biological notes. No data are available.

Distribution. Algeria, Tunisia, Egypt, Israel.

Non-type specimens examined. ALGERIA: Constantine (1, MNHN) . TUNISIA: Tunisia (1, MNHN) ; Tkala , 2.IV.1994, Nàdai leg. (1, APCB) . EGYPT: Aboukir , 26.VI.1914, Alfieri leg. (1, MNHN; 1, NHMB) . ISRAEL: Haifa, Mount Carmel , 18.III.1933, Schatzmayr leg. (2, MSNM) ; 50 km S Tel Aviv, 23.V.1992, Sugoniaev leg. (1, ZISP) .

Figures

FIGURES 10–18. Habitus of (10) Mecinus longulus; (11) M. tychioides; (12) M. labilis; (13) M. plantaginis; (14) M. alboscutellatus alboscutellatus; (15) M. paratychioides; (16) M. linnavuori; (17) M. desertorum; (18) M. marina. Not to the same scale.

FIGURES 43–57. Rostrum in lateral view of (43) Mecinus pascuorum, male; (44) idem, female; (45) M. ictericus, female; (46) M. caucasicus, male; (47) idem, female; (48) Mecinus variabilis, male; (49) idem, female; (50) M. haemorrhoidalis, male; (51) idem, female; (52) M. seriatus, female; (53) M. longulus, female; (54) M. tychioides, male; (55) M. labilis, male; (56) idem, female; (57) M. plantaginis, male. Scale bar = 0.5 mm.

FIGURES 108–120. Penis in dorsal and lateral view of (108) Mecinus pascuorum; (109) M. crassifemur; (110) M. ictericus; (111) M. latiusculus; (112) M. caucasicus; (113) M. variabilis; (114) M. tychioides; (115) M. haemorrhoidalis; (116) M. longulus; (117) M. labilis; (118) M. plantaginis; (119) M. alboscutellatus alboscutellatus; (120) M. paratychioides. 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.