Distribution, life history, host specificity and suitability of an undescribed Chrysolina species (Coleoptera: Chrysomelidae) for the biological control of Chrysanthemoides monilifera (Compositae).
In host specificity tests using 81 plant species from 27 families, an undescribed species of Chrysolina completed its development only on Chrysanthemoides monilifera [C. moniliferum], a serious weed of native vegetation in Australia. Minor exploratory feeding, mostly by adults, occurred on 35 plant species. Chrysolina sp. is restricted to the eastern Cape Province of South Africa where it occurs on Chrysanthemoides monilifera pisifera [C. moniliferum pisiferum ?], a subspecies not yet recorded in Australia. C. m. moniliferum and C. m. rotundata [C. moniliferum rotundatum], both naturalized in Australia, were accepted as hosts by Chrysolina sp., but adult emergence was lower on the latter subspecies. A climate comparison between a site location for Chrysolina sp. and stations within the Australian distribution of Chrysanthemoides moniliferum identified potential release sites that may be suitable for the insect. Chrysolina sp. was approved for release in Australia in 1989 and releases were initiated in 1990.