Mecinus alboscutellatus atratulus (Solari)

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 : 35-36

16b. Mecinus alboscutellatus atratulus (Solari)

Gymnetron alboscutellatum var. atratulum Solari, 1933: 164 . Porta, 1934: 191. Abbazzi & Osella, 1992: 379. Osella et al., 2005.

Type locality. Gran Sasso (Abruzzo, Italy).

Type series. This taxon was described from specimens from Gran Sasso ( Italy: Abruzzo) as a variety of M. alboscutellatus , which can be considered at a subspecific rank according to Art. 45.6.4 of ICZN (1999). We examined seven syntypes ( MSNM), all labelled “ Abruzzo, G. Sasso, 3.8.24, A. Fiori / nato da frutti di Plantago montana / Gymnetron v. atratulum m., det. F. Solari ”. Moreover, in the last data-label of one specimen is written “typus! ♂ “, in another specimen “typus! ♀ “ and in the five others “cotypus“. However, since Solari did not designate a holotype in his original description, we here designate the specimen with the label “typus! ♂ ” as the lectotype.

Redescription. As the nominal subspecies except that the antennae and tarsi are blackish brown in colour.

Variability. Length mm 1.7–2,1. Sometimes the sides of the elytra are only weakly rounded.

Biological notes. The host plant is probably Plantago atrata Hoppe (= P. montana Lam. ), from the fruits of which the specimens of the type series emerged ( Solari 1933). However Osella et al. (2005) reported that they collected adults of atratulus on Helianthemum sp. and found some specimens of this plant with galls produced by larvae of this subspecies. It is noteworthy that M. alboscutellatus was also collected on Helianthemum in France. Since the host plants of many species of Mecinus belong to the genus Platago, it is possible that both subspecies can parasitize Helianthemum when Plantago is not available.

Distribution. This subspecies is only known from mountains of the Abruzzi Apennines (central Italy) at high altitude.

Non-type specimens examined. ITALY (Abruzzo): Gran Sasso , 22.VI.1874, Gestro leg. (1, MSNG) ; Gran Sasso , 2200 m, 20.VI.1930, Tasso, Schatzmayr & Koch legg. (18, MSNM; 4, CPCM) ; Gran Sasso, Albergo Campo Imperatore , 1900 m, 10.VIII.1969, Caldara leg. (1, DEIM; 1, CPCM; 6, RCCM) ; Gran Sasso, Campo Imperatore, S. Egidio , 1600 m, 27.VI.1984, Abbazzi leg. (3, PACF) ; Gran Sasso, Campo Imperatore , 1600–2000 m, 24.IX.1994, Osella leg. (2, GOCA) ; Gran Sasso, Campo Pericoli , 2300 m, 25.VII.1998, Osella leg. (11. GOCA) ; Gran Sasso, Monte Aquila , 2000 m, 22.X.1995, Osella leg. (1, GOCA) ; Gran Sasso, Monte Portella , 5.VIII.1924, Fiori leg. (1, MSNG) ; Gran Sasso, Monte Portella , 2300 m, 4.IX.1971, Tamanini leg. (1, GOCA) ; Gran Sasso, Monte San Franco , 2000 m, 30.V.1986, Colonnelli leg. (7, ECCR; 1, GOCA) ; Gran Sasso, Sorgente San Franco , 1650 m, 7.VII.1990. Colonnelli leg. (1, ECCR) ; Gran Sasso, Pendici Vado di Corno , 1900–2000 m, 20.VI.1994, Cornacchia & Toledano legg. (1, PCCP) ; Gran Sasso, Pietracamela , 24.VI.1926, Pretner leg. (3, MHNG) ; Gran Sasso, Rifugio Duca degli Abruzzi , 2300–2400 m, 20.VI.1994, Cornacchia & Toledano legg. (1, PCCP) ; Monti della Laga, Cima Lepri , 2300 m, 26.VIII.1998, Osella leg. (1, GOCA) ; Monti della Laga, Monte Gorzano , 2000– 2300 m, 19.VI.1994, Cornacchia & Toledano legg. (2, PCCP) ; Monti della Laga, Pizzo di Sevo , 1800–2400 m, 19.VI.1973, Cornacchia leg. (1, PCCP) .

Remarks and comparative notes. According to the available data, M. alboscutellatus s. l. appears to be a relict species with Euro-Boreoalpine distribution ( Caldara & Alonso-Zarazaga 2010). This species is mainly characterized by a short oval body with the integument of pronotum and elytra completely black and covered with recumbent somewhat sparse scales. These characters allow M. alboscutellatus s. l. to be separated from all other species of Mecinus .

Regarding the subspecies atratulus, Solari quoted that this taxon differs from M. alboscutellatus s. str. by weakly more elongate elytra, with parallel to weakly rounded sides, by antennae, tibiae and tarsi blackish brown. After the study of many specimens from Val d'Isére and especially from Abruzzo, we have ascertained that atratulus differs constantly from the nominal subspecies only by antennae and tarsi being darker in colour. However, due to the geographical isolation, presently the rank of this taxon as a subspecies appears justified. Molecular studies are in progress in order to better clarify the taxonomic value of atratulus (I. Toševski pers. comm.).