DISTRIBUTION, LIFE-HISTORY AND HOST-SPECIFICITY OF CHRYSOLINA-PICTURATA AND CHRYSOLINA SP B (COLEOPTERA, CHRYSOMELIDAE), 2 BIOLOGICAL-CONTROL AGENTS FOR CHRYSANTHEMOIDES-MONILIFERA (COMPOSITAE)

The southern African shrubs Chrysanthemoides monilifera monilifera and C. m. rotundata (Compositae) are serious weeds of native vegetation i n Australia and are targets for classical biological control. in host specificity tests using 69 species from 25 families, two leaf-feeding chrysomelid beetles, Chrysolina picturata (Clark) and Chrysolina sp. B , were able to complete development on only Chrysanthemoides monilifer a and C. incana. The subspecies Chrysanthemoides m. monilifera was the superior host for both Chrysolina picturata and Chrysolina sp. B. Fee ding and limited development of both species occurred on Calendula off icinalis; limited development by Chrysolina picturata larvae occurred on Helianthus annuus, Tussilago farfara and Cymbonotus priessianus. Ch rysolina picturata and Chrysolina sp. B are considered to be Chrysanth emoides-specific and have been approved for release in Australia. Pote ntial release sites for both Chrysolina species were chosen by compari ng the climate of the insects' African distribution with climate stati ons within the range of Chrysanthemoides monilifera in Australia. Chry solina picturata and Chrysolina sp. B are suited for release within th e western distribution of Chrysanthemoides m. monilifera in coastal ar eas of south eastern South Australia.