Mecinus labilis (Herbst)

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 : 29-31

13. Mecinus labilis (Herbst)

Figs 12 , 55–56 , 117 , 160

Curculio labilis Herbst, 1795: 244 .

Gymnetron labile (Herbst) . Gyllenhal, 1838: 751. H. Brisout de Barneville, 1862: 636. Desbrochers des Loges, 1893: 41. Rey, 1894: 74. Reitter, 1907: 19. Hustache, 1931: 410. 417. Hoffmann, 1958: 1280, 1286. Smreczyṅski, 1976: 29. Lohse & Tischler, 1983: 266.

Mecinus labilis (Herbst) . Caldara, 2001: 183.

Curculio tricolor Marsham, 1802: 259 (non Scopoli, 1772, nec Linnaeus, 1790).

Gymnetron tricolor (Marsham) . Hardy & Bold, 1852: 200. H. Brisout de Barneville, 1862: 636.

Cleopus obliquus Sturm, 1826: 120 (nomen nudum).

Gymnetron vittatum Betta, 1857: 61 . Caldara & Colonnelli, 2012: 90.

Gymnetron labile var. brevicrinitum Reitter, 1907: 19 ; 1916: 227. Hoffmann, 1958: 1286 (infrasubspecific name).

Type locality. Berlin ( Germany).

Type series. At ZMHB, near a card with written “Labilis Schön.*, Curculio l. Ht., Rhynchaenus tricolor Gyll., Ber. Schüp. ”, we have found eight syntypes of this species labelled as follows: “54720 [printed]” (one male, lectotype here designated); “Hist. Coll. 54720 [handwritten]” (3 males and 3 females, paralectotypes); “labilis, C. lab. Hb., R. tricol. Gyl. / Hist. Coll. 54720” (1 male, paralectotype).

Synonyms. Curculio tricolor was described from Britannia (currently the United Kingdom) without other indications. In Marsham's collection ( BMNH) there is a syntype of this species, corresponding well with the original description (R. T. Thompson pers. comm.). As usually considered, it is a synonym of M. labilis .

Sturm (1826) quoted the unpublished name Cleopus obliquus , without an associated description and which was subsequently always considered as synonymous with M. labilis . Therefore this name is a nomen nudum (ICZN 1999, Art 12.1).

Gymnetron vittatum was described by Betta based on specimens from Lombardy (northern Italy) no longer available. According to the original description Caldara & Colonnelli (2012) designated the neotype of this species and synonymized it with M. labilis .

The variety brevicrinitus of M. labilis was described from specimens from Munich ( Germany), Velebit ( Croatia) and Araxesthal (Caucasus) characterized by seta-like elytral scales shorter than in the typical form ( Reitter 1907) and subsequently placed together with this ( Reitter 1916). Accordingly, this name must undoubtedly be considered as infrasubspecific (ICZN 1999 Art. 45.6.1) and therefore is unavailable (ICZN 1999 Art. 45.5).

Redescription. Male. Length 1.8 mm. Body: somewhat short, oval, stout ( Fig. 12 ). Rostrum: black with reddish apex, moderately long (Rl/Pl 0.85), subcylindrical; in lateral view moderately curved in basal half then straight ( Fig. 55 ); in dorsal view with sides weakly narrowed in basal third then parallel, with hardly visible scrobes, moderately striate-punctured to near apex, shining, in basal half with recumbent to erect, sparse, whitish, long (l/w 5–10), seta-like scales. Head: frons slightly wider than rostrum at base, without fovea; eyes moderately convex. Antennae: reddish with blackish brown club, inserted just before middle of rostrum; scape very short, twice as long as wide; funicle distinctly longer than scape, segment 1 twice as long as wide, stouter and 2.5x longer than segment 2, which is about as long as wide, segments 3–5 gradually more transverse; club short, oval, segment 1 shining and almost glabrous. Pronotum: black, with dense and regular punctures, intervals between punctures narrow, smooth and shining, clearly visible between recumbent to erect, sparse, whitish and light brown, long (l/w 6–10), seta-like scales; distinctly transverse (Pw/Pl 1.47), with moderately rounded sides, with moderately prominent apical constriction, widest in basal third, moderately convex. Elytra: reddish except base, interstria 1, sides and two oblique bands (basal half and apical half) from interstria 1 to 7, which are black; moderately long (El/ Ew 1.29), suboval, at base weakly concave, moderately wider than pronotum (Ew/Pw 1.24), widest in basal half, distinctly convex on disc; interstriae clearly visible between recumbent to suberect (the latter arranged in a somewhat regular row), moderately dense, white and light brown, long (0.5–1.2x as long as width of interstria; l/w 6–10), seta-like scales; striae hardly visible, as wide as half of interstria, with a row of scales similar to shorter ones covering interstriae. Legs: moderately stout, with subrecumbent to erect, sparse, whitish, seta-like scales, which are slightly shorter than width of tibia; femora black and reddish, stout, with very small tooth; tibiae reddish, moderately slender, protibiae with apical part of ventral surface weakly directed outward; unci black, stout, all equal in length and shape; tarsi reddish, tarsomere 1 1.3x longer than wide, tarsomere 2 moderately transverse, tarsomere 3 bilobed and distinctly wider than tarsomere 2, onychium as long as tarsomeres 1–3 taken together; claws blackish, equal in length, fused in basal half. Venter: metasternum black, clearly visible between recumbent to subrecumbent, sparse, whitish, long, hair-like scales; mesothoracic epimera and meso- and metathoracic episterna with moderately dense, whitish, seta-like scales and wider, bifid to fringed scales; abdomen black, with somewhat dense and regular punctures, which are clearly visible between subrecumbent to suberect, sparse, whitish and light brown, long, hair-like scales; ventrites length ratio 1–2/3–4 2.06. Penis: fig. 117.

Female. As in male except rostrum longer (Rl/Pl 0.96), straighter ( Fig. 56 ), smooth and shining, sparcely punctured, in lateral view thinner and cylindrical from antennal insertion to apex, in dorsal view weakly widened in apical third, antennae inserted at basal third of rostrum, femora with indistinct tooth. Sternite 8: as in M. pascuorum ( Fig. 144 ). Spermatheca: fig. 160.

Variability. Length 1.7–2.0 mm. Sometimes the oblique black bands on the elytral integument are reduced. The scales of dorsal vestiture vary slightly in length and thickness.

Remarks and comparative notes. This species is very closely related to M. bonnairei , from which it differs by the less dense elytral vestiture, with scales regularly arranged on elytra, the slightly narrower body with weakly longer elytra and slightly shorter and weakly more curved rostrum at its base. The pattern of the elytral vestiture and the shape of the rostrum of the female allow to separate these two species from all the others.

Biological notes. Larvae feed on Plantago lanceolata L., where they pupate in the collar without causing modification externally visible ( Hoffmann 1958).

Distribution. Europe, Caucasian States, Turkey.

Non-type specimens examined. SPAIN: Andalucía, Granada, Cortichuela, Sierra Nevada , 1650 m, 4.VII.1984, Alonso-Zarazaga leg. (1, AZCM) ; Aragón, Moncayo , 1000–1500 m, 20.V.1999, Talamelli leg. (1, FTCM) ; Castilla-La Mancha, Albacete, Sierra de Alcaras, Puerto del Barrancaso , 1000 m, 19.V.1990, Audisio & Biondi legg. (1, GOCA) ; Comunidad Valenciana, Alicante, Callosa , 20.IV.1980, Meregalli leg. (1, MMCT) ; Comunidad Valenciana, Valencia, Alto de Tona, Caroch hill, 1126 m, 24.VI.1997, Borovec leg. (2, RBCS) ; País Vasco, San Sebastian, Monte Igueldo , 22.VII.1959, Burlini leg. (1, GOCA) ; Pais Vasco, Álava, Mezkia , 21.V.2007, Ugarte & Salgueira legg. (1, USCA) ; Pais Vasco, Álava, Musitu , 1.VIII.2010, Ugarte & Salgueira legg. (1, USCA) ; Pais Vasco, Guipuzkoa , Tximistarri, Ugarte & Salgueira legg. (1, USCA) . FRANCE: Île de France , Fontainebleau (1, BMNH) ; Northern-Pas-de-Calais, Lille , V.1929 (1, LMCP) ; Provence-Alpes-Côte d'Azur, Hyères (1, BMNH) . SWITZERLAND: Canton Ticino, Stabio , 21.I.1951, Cadamuro leg. (1, GOCA) . GERMANY: Bayern, Augsburg, Kissing , 24.VIII.1988, Riedel leg. (3, ARCK) ; Bayern, Haimhausen Kreis, Dachau , 4.I.1977 (1, GOCA) ; Niedersachsen, Marienau , Letzner leg. (5, DEIM) ; Sachsen, Leipzig , 30.V.1958, Dieckmann leg. (1, LMCP) ; Thüringen, Arnstadt , 7.VI.1940. Liebmann leg. (4, DEIM) ; Thüringen, Plaue , 1.VIII.1921, Liebmann leg. (1, DEIM) . RUSSIA: Dagestan (1, ZISP) . UKRAINE: Ascania-Nova (1, ZISP) . Moldova: Moldova (1, ZISP) ; Bessarabia , 1893, Horvath leg. (1, HNHM) . HUNGARY: Hungaria (2, MSNM) . Austria: Wien , Winkler leg. (2, MSNV; 1, LMCP) ; Neusiedlersee , Hoffmann leg. (1, LMCP) ITALY: Piemonte, Torino, Brunetta di Susa , 27.VII.1974, Meregalli & Alonso-Zarazaga legg. (1, AZCM; 1, MMCT) ; Lombardia, Pavia, Santa Margherita Staffora , 20.V.2001, Diotti leg. (1, LDCC) ; Veneto, Verona, Mezzano , 12.V.1976, Osella leg. (3, GOCA) ; Venezia Giulia , Trieste (5, MSNV) ; Liguria, La Spezia, Zignago , 2.VII.1981, Failla leg. (3, MSNF) ; Emilia Romagna, Bologna, Monte Adone , 6.VIII.1988, Pierotti leg. (1, GOCA) ; Emilia Romagna, Forlì-Cesena, Sarsina, Monteriolo , 13.II.1977, Sama leg. (1, GOCA) ; Emilia Romagna, Modena, Moscardini leg. (1, LMCP); Toscana, Firenze , 25.VI.1971, Failla leg. (1, MSNF) ; Toscana, Firenze, Paternò , 12.VI.1976, Abbazzi leg. (1, PACF) ; Toscana, Livorno, Isola d'Elba , 1908, Paganetti leg. (2, MSNM) ; Livorno, Isola d'Elba, Villa Napoleone , 6.X.1988, Bellò leg. (1, GOCA) ; Toscana, Siena , 20.VII.1970, Osella leg. (1, GOCA) ; Umbria, Perugia, Monte del Lago (1, GOCA) ; Lazio, Roma, Monti della Tolfa , 12.V.1998, Angelini leg. (1, FACF) ; Abruzzo, L'Aquila, Avezzano, Monte Salviano , 950 m, 1.VI.1996, Osella leg. (1, GOCA) ; Abruzzo, L'Aquila, Pietracquaria, Monte Salviano , 3.IX.1999, Osella leg. (1, GOCA) ; Abruzzo, Teramo, Laga, Frattoli , 1050 m, 2.VI.1996, Cappelletti leg. (1, GOCA) ; Abruzzo, Teramo, Monte Foltrone , 28.VII.1979, Bologna leg. (1, GOCA) ; Molise, Isernia, Capracotta , 19.VI.1996, Osella leg. (1, GOCA) ; Molise, Isernia, Castiglione Messer Marino , 8.VII.1997, Osella leg. (1, GOCA) ; Puglia, Foggia, San Cataldo , 27.IV.1976, Gianasso leg. (1, MMCT) ; Puglia, Taranto, Castellaneta , 2.VII.1984, Platia leg. (1, GOCA) ; Basilicata, Matera , 14.IX.2001, Angelini leg. (1, FACF) ; Basilicata, Matera, Ferrandina , 29.V.1976, Montemurro leg. (1, LDCC) . ITALY (Sicily): Siracusa, Buscemi , 7.VI.1986, Bellò leg. (1, GOCA) . SLOVENIA: Ljubljana, Grabowski leg. (2, MMCT) . CROATIA: Dalmatia, Drvenik , 12.VI.1989, Borovec leg. (1, RBCS) . Serbia: Fruška gora, 11.VI.1985, Donev leg. (1, GOCA) . BOSNIA AND HERZEGOVINA: Bosnia , Bokor leg. (1, GOCA) . ROMANIA: Orsova , Kusanpass (1, MSNV) . GREECE: Macedonia, Agios Vrondrou , 30.VI.1997, Winkelmann leg. (1, HWCB) ; Corfu , 1913, Kramer leg. (1, ZMHB) . BULGARIA: Belasiza , 1000 m, 13.VI.1978, Angelov leg. (1, GOCA) ; Melnik , 16.VI.1978 (1, MMCT) ; Strandza, Slivovo , 20.VI.1978, Angelov leg. (1, GOCA; 2, MMCT) ; Zwezdec , 16.V.1985, Angelov leg. (1, GOCA) ; Trakia, Stojkovo , 11.V.1989, Podlussány leg. (1, APCB) . ARMENIA: Abovian, Hatsavan , 17.VI.1994, Kalashian leg. (1, FTCM) ; Syumik , 3 km S Goris, 11.VII.2001, Kalashian leg. (1, MMCT) . AZERBAIDJAN: Lenkoran, Leder leg. (1, HNHM) . GEORGIA: Araxesthal , Leder & Reitter legg. (2, HNHM) . TURKEY: Ankara, Kizilcahaman , 16.VII.1971, Osella leg. (1, GOCA) ; Bitlis, Tatvan, Ahlat N Van Gölü , 10.VII.1996, Tyrner leg. (1, RBCS) ; Bolu, Abant , 1000 m, 21.VI.1975, Osella leg. (1, GOCA) ; Çanakkale, Besika Bay (2, BMNH) ; Kastamonu, Aliaga-Kure , 14.VII.1996, Bayer & Winkelmann legg. (1, HWCB) ; Kastamonu N, 8 km N Seydiler , 14.VII.1996, Bayer leg. (1, CBCB) .

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 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.

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.