Diplapion westwoodi ( Wollaston, 1864 )

Morris, Michael G., Sw, London & Dt, Dorset, 2011, The Apionidae (Coleoptera) of the Canary Islands, with particular reference to the contribution of T. Vernon Wollaston, Acta Entomologica Musei Nationalis Pragae 51 (1), pp. 157-182 : 171-172

Diplapion westwoodi ( Wollaston, 1864)

( Fig. 6 )

There seem to have been no published records of this species, which has been found only in Gran Canaria, since Wollaston’s original discovery in 1858 ( WOLLASTON 1864). No further records were given by LINDBERG & LINDBERG (1958), by BRITO & OROMÍ (1986) nor by GURREA & SANZ (2000), while WANAT (1995) was able to examine only one individual in addition to the type material. Apart from its origin in Gran Canaria, and current location, data on this specimen were not given. However, Mr A. P. Fowles (pers. comm.) took D. westwoodi in the Roque Noble area on 4 January 1995. I found one female specimen there on 26 February 1997, but the weevil was abundant near La Yedra on 1 March 1997 and again on 13 November 1999. My specimens all came from an unidentified species of Argyranthemum and it is assumed that this is the host, other species of Diplapion being also associated with Asteroideae-Anthemideae ( Asteraceae ) (ALONSO- ZARAZAGA 1990a). In January 2004 D. westwoodi was found to be abundant in Gran Canaria. It was recorded from seven separate sites in the central part of the island (Lomo Mangrera, near Cruz de Tejeda, Hoya de la Montaña, Las Lagunetas, El Portillo, Montaña de las Pilas, Ariñez) and was particularly numerous at the first site. It is surprising that the species has been previously regarded as rare. The host, in every case, was Argyranthemum adauctum ssp. canariense , identified by elimination and from distributional data in BRAMWELL & BRAMWELL (1974) rather than structural characteristics, as fruits were not present at this time of year. Argyranthemum , which is a very speciose genus, has representatives in other Canarian islands (and a few in other parts of Macaronesia), including other subspecies of A. adauctum , so that it is possible that D. westwoodi occurs elsewhere in the Canaries. It is known from Tenerife (M. A. Alonso-Zarazaga, in litt.).

There are 2 male and 2 female specimens in Wollaston’s BMNH collection. One male is labelled ‘lectotype’ (desig. Dr. M. Wanat, 15.04.1986) and one female ‘paralectotype’ with the same designation data ; this latter specimen also bears a ‘ Type’ label. The lectotype and paralectotype designations were published by WANAT (1995). All the specimens are, of course, from Gran Canaria. Although there is a female example of D. westwoodi (with labels ‘det. Wagner’ and ‘det. Wanat’) in the BMNH General Collection labelled ‘ Madeira’, this is evidently an error by some subsequent worker, as the card on which the specimen is mounted bears the ‘dark indigo’ colour at its base, indicating that it is an original Wollaston specimen from Gran Canaria. There are 4 male and 5 female specimens from Gran Canaria in the OUMNH series .

Figures

Figs. 5–8. Habitus of the Apionidae of Canary Islands. 5 – Ceratapion calcaratum (Wollaston, 1864), lectotype, Wollaston Coll. (BMNH); 6 – Diplapion westwoodi (Wollaston, 1864), paralectotype, Wollaston Coll. (BMNH); 7 – Lepidapion senex (Wollaston, 1864), lectotype, Wollaston Coll. (BMNH); 8 – Taeniapion atlanticum (Uyttenboogaart, 1935), author’s Coll.