Mecinus collaris

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 : 64-66

Mecinus collaris group

Diagnosis. Rostrum short and wide, straight in lateral view; scrobe not reaching anterior margin of eye. Elytra elongate. Broad scales densely covering base of pronotum, epimera and episterna.

Remarks and comparative notes. This species is easily distinguishable from all other species of Mecinus by the characters quoted in the diagnosis of the group. Presently it is unclear to which other species it is more closely related. The other species with short and straight rostrum, like those of the M. simus group, do not apparently share other synapomorphyes with M. collaris .

36. Mecinus collaris Germar

Figs 34 , 80 , 135 , 152 , 171

Mecinus collaris Germar, 1821: 318 . Rosenschoeld, 1838: 779. Bedel, 1885: 146; 1887: 309; 1888: 426; 1923: 69. Desbrochers des Loges, 1893: 62. Rey, 1894: 75. Reitter, 1907: 8; 1916: 225. Hustache, 1931: 402, 404. Hoffmann, 1958: 1266, 1268. Angelov, 1971: 116, 119. Smreczyṅski, 1976: 25. Lohse & Tischler, 1983: 260. Caldara, 2008: 133.

Curculio cinctus Rossi, 1790: 125 (non Drury, 1782 nec Geoffroy, 1795). Caldara, 2008: 126.

Mecinus curvirostris Petri, 1926: 203 . Endrǒdi, 1970: 259.

Type locality. Berlin ( Germany).

Type series. This species was described from specimens from Austria and Saxony ( Germany), which were not found in Germar's collection nor in other collections examined. Therefore , according to Art. 75 of ICZN (1999), Caldara (2008) designated a neotype for this taxon.

Synonyms. Rossi (1790) described Curculio cinctus from specimens from “Etruria” (an ancient area of central Italy presently included in Toscana, part of Umbria and Lazio) a name no longer in use. According to Art. 75 of ICZN (1999), Caldara (2008) designated a neotype for this taxon (type locality: Foligno, Umbria, Italy). Although it was described earlier than collaris , Rossi's name is invalid since it is junior homonym of C. cinctus Drury, 1782 and C. cinctus Geoffroy, 1785 ( Caldara 2008) .

Mecinus curvirostris was described from a single specimen collected at Schässburg (currently Sighisoara, Romania) and was considered very similar to M. collaris , from which it should differ by the slightly stouter rostrum, which is slightly longer and weakly curved, and the almost spherical pronotum ( Petri 1926). Endrôdi (1970) synonymized this species with M. collaris based on the original description, and reported that the type is missing. Actually the type is deposited at Muzeul National Brukenthal (Sibiu, Romania) in Petri's collection. It was recently examined by E. Colonnelli (pers. comm.), who sent us some photographs, whose examination has made clear that M. curvirostris is the same species as M. collaris and therefore we can confirm the synonymy proposed by Endrôdi.

Redescription. Male. Length 2.9 mm. Body: long, subcylindrical, moderately stout ( Fig. 34 ). Rostrum: black, short (Rl/Pl 0.71), subconical; in lateral view almost straight, moderately narrowed at apex; in dorsal view with sides slightly gradually narrowed from antennal insertion to apex, with moderately visible scrobes, distinctly punctured and moderately striated to near apex, in basal half with recumbent, sparse, whitish, moderately long (l/w 3–5), seta-like scales. Head: frons weakly narrower than rostrum at base, without fovea; eyes nearly flat. Antennae: reddish brown, inserted between median third and apical third of rostrum; scape moderately long, 4.0x longer than wide; funicle about as long as scape, segment 1 1.5x longer than wide, slightly stouter and about as long as segment 2, which is 1.5x longer than wide, segments 3–5 gradually more transverse; club long, oval, with segment 1 about as pubescent as others. Pronotum: black, with dense and regular punctures, intervals between punctures smooth and shining, clearly visible between scales sparse, white, long (l/w 4–7), seta-like, recumbent and hidden at base by scales dense, whitish to ochraceous, short (l/ w 1.25 –2), oval (especially in basal third and sides), fringed, recumbent; weakly transverse (Pw/Pl 1.18), with weakly rounded sides, with weakly prominent apical constriction, widest at basal third, moderately convex. Elytra: black; long (El/Ew 1.64), at base distinctly concave, moderately wider than pronotum (Ew/Pw 1.27), with moderately rounded sides from base, widest in apical third, somewhat convex on disc; interstriae clearly visible between recumbent, sparse, whitish, long (0.40– 0.60x as long as width of interstria; l/w 5–8), seta-like scales, arranged in 2–3 irregular rows; striae clearly visible, one third narrower than interstriae, with regular punctures and with intervals between punctures on the same plane of interstriae, with a row of scales similar to those of interstriae. Legs: stout, with scales sparse, whitish, distinctly shorter than width of tibia, seta-like, recumbent; femora black, subclavate, with small tooth; tibiae blackish with reddish apex, short; protibiae with apical part of ventral surface weakly directed outward; unci blackish, stout, all equal in length; tarsi brownish, short, tarsomere 1 1.5x longer than wide, tarsomere 2 about as long as wide, tarsomere 3 bilobed and distinctly wider than tarsomere 2, onychium as long as tarsomeres 1–3 taken together; claws dark brown, equal in length, fused in basal half. Venter: metasternum black, clearly visible between recumbent, sparse, whitish, moderately long, seta-like scales; mesothoracic epimera and meso- and metathoracic episterna with dense, white to ochraceous, short, fringed scales; abdomen black with ventrite 5 reddish at apex, with somewhat dense and regular punctures, which are clearly visible between recumbent, sparse, whitish, moderately long, seta-like scales; ventrites length ratio 1–2/3–4 1.90. Penis: fig. 135.

Female. As in male except rostrum slightly longer (Rl/Pl 0.77) ( Fig. 80 ), more sparsely striate-punctured, antennae inserted just in front of middle of rostrum. Sternite 8: fig. 152. Spermatheca: fig. 171.

Variability. Length 2.7–3.2. The colour of the wide scales at base of pronotum, which sometimes are sparse and almost indistinct, varies from whitish to orange. The colour of tarsi varies from reddish to dark brown. The elytra varies somewhat in width (El/Ew 1.60–1.70).

Remarks and comparative notes. This species is unique in Mecinus , being characterized by long elytra and with whitish to orange, wide scales covering the base of the pronotum, the epimera and the episterna.

Biological notes. Larvae feed on various species of Plantago , generally P. maritima L., but also P. coronopus L., P. lanceolata L., P. major L. and P. media L., where they induce oblong galls in floral spikes. They are parasitized by Micromelus pyrrhogaster Walker, 1933 belonging to Hymenoptera Chalcididae ( Hoffmann 1958) .

Distribution. Europe, Caucasian States, Middle East, Russia to Far East, Kazakhstan, Mongolia ( Hoffmann 1958; Arzanov 2000).

Non-type specimens examined. About 150 specimens from the United Kingdom, Spain, France, Poland, Germany, Czech Republic, Slovakia, Hungary, Italy, Serbia, Romania, Russia, Mongolia .

Figures

FIGURES 28–36. Habitus of (28) Mecinus baridioides; (29) M. comosus; (30) M. simus; (31) M. pirazzolii; (32) M. vulpes; (33) M. pipistrellus; (34) M. collaris; (35) M. sicardi; (36) M. janthinus. Not to the same scale.

FIGURES 78–87. Rostrum in lateral and dorsal view of (78) Mecinus comosus, male; (79) idem, female; (80) M. collaris, female; (81–82) M. simus, female; (83) M. pirazzolii, female; (84) M. pipistrellus, female;; (85) M. vulpes, female; (86) M. sicardi, male; (87) idem, female. Scale bar = 0.5 mm.

FIGURES 133–143. Penis in dorsal and lateral view of (133) Mecinus vulpes; (134) M. pipistrellus; (135) M. collaris; (136) M. lixoides; (137) M. sicardi; (138) M. janthiniformis; (139) M. barbarus; (140) M. janthinus; (141) M. heydenii; (143) M. tavaresi; (142) M. aubei. 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.