Canadian Forest Service Publications
Life cycle and host specificity of the heliotrope Pachycerus cordiger ( = _Madidus Auct.) [Col.; curculionidae]. 1990. Huber, J.T.; Vayssieres, J.F. Entomophaga 35:475-484.
Issued by: Great Lakes Forestry Centre
Catalog ID: 34903
CFS Availability: PDF (request by e-mail)
Pachycerus cordiger Germar (Curculionidae: Cleonini) is a potential agent for the biological control of Heliotropium europaeum L. (Boraginacea in Australia. Adults feed on the leaves and larvae feed on the main roots of the weed within an earthen cell. These is one generation per year. Adults overwinter in the cells before emerging in the spring when they begin to feed, mate and oviposit on their host plants from late May until late July. Seven Boraginaceae and 31 economically important corp species were tested using adults and 1st instar lavae. P. cordiger was found to be specific to the Boraginaceae. Field observations strongly suggested that the weevil is restricted to summer-annual Helioptropium species. A widespread egg parasite, Caenocrepis? bothynoderi Gromakov [Hymenoptera: Pteromalidae] caused up to 18% mortality.