Control of Toadflax by Brachypterolus pulicarius (L.)(Coleoptera: Nitidulidae) and Gymnaetron antirrhini (Payk.) (Coleoptera: Curculionidae) in Canada

Publisher Website
Google Scholar
Abstract
The principal insects that attack toadflax (Linaria vulgaris Mill.) in Canada are Brachypterolus pulicarius (L.), a flower-eating nitidulid, and Gymnaetron antirrhini (Payk.), a seed-eating weevil. B. pulicarius was found in 1953 in all provinces of Canada but G. antirrhini was apparently absent from Saskatchewan and Alberta, the two provinces where the spread of toadflax was causing alarm. Thus the seriousness of the toadflax seemed to be related to the absence of G. antirrhini. In an artempt to correct this situation Smith (1959) collected 4,000 adult G. antirrhini and released them in mid-July, 1957, at Marsden, Saskatchewan, and Codesa, Alberta. However, it now appears that the rapid spread of toadflax occurred in the absence of B. pulicarius and that this beetle is more valuable than first thought. This paper discusses the role of B. pulicarius and the results of introducing G. antirrhini.