Target pest: Coleophora spissicornis (Lepidoptera: Coleophoridae), banded clover casebearer
Agent introduced: Bracon osculator (Hymenoptera: Braconidae)
Near MontmÃ©dy, France
Cameron et al. (1989) - Bracon osculator was imported in 1952 as parasitised Coleophora trifolii host larvae collected near MontmÃ©dy, France. Approximately 100 adult wasps emerged and were released. A 1955 importation of 5,000 parasitised C. trifolii from MontmÃ©dy also contained some B. osculator. The five females and two males which emerged were destroyed after failing to parasitise New Zealand Coleophora. After a limited number of specimens were examined, there was some doubt that the species imported in 1955 was in fact B. osculator.
Late-1952 or early-1953
Cameron et al. (1989) - approximately 100 adults that had emerged from imported hosts were released near Nelson, South Island in late-December 1952 (1953?), at a time suitable hosts would have been available in the field. A further several hundred host larval cases containing parasitised larvae [apparently a mix of locally-collected Coleophora spp. and unemerged C. trifolii from the August 1952 importation] were placed in the field in March 1953; some of these would have contained B. osculator.
Cameron et al. (1989) - there have been no recoveries of B. osculator.
Cameron PJ, Hill RL, Bain J, Thomas WP (1989). A Review of Biological Control of Invertebrate Pests and Weeds in New Zealand 1874-1987. Technical Communication No 10. CAB International Institute of Biological Control. DSIR Entomology Division. 424p.