June 2002. New Caledonia asked about the natural enemies (biological control) of the cactus, Acanthocereus pentagonus. It is present in New Caledonia, but a native to Southern USA, Central and South America.
Members provided information about two insects that have been used to control this cactus.
1. A mealybug from South America, Hypogeococcus pungens Granara de Willink, has been used successfully to control weed cacti (Eriocereus spp. and Acanthocereus pentago) in Australia (Queensland). The mealybug has been recorded also from quite a few Caribbean islands and Spain in recent years. It feeds on a range of cacti and some other succulent and fleshy plants.
CABI Bioscience station in Trinidad & Tobago could collect and screen specimens for a biological control
programme if required. The message was copied to CABI for information, which could provide more detailed distribution information for H pungens, and references on the Queensland story, if required.
2. Hypogeococcus festerianus (Lizer y Trelles) is recorded as having been released in Queensland for the control of Acanthocereus pentagonus. It has also been used to control Harrisia martinii and H bonplandii in Australia, and Cerus jamacaru and H martinii in South Africa. Note, that the cactus genus Eriocereus is now referred to as Harrisa. Queensland Department of Natural Resources and Mines should be contacted.