Passionvine hopper, Scolypopa australis (Walker) (Hemiptera: Ricaniidae), egg parasitism by Aphelinidae (Hymenoptera) in New Zealand.

Abstract

The distributions and aspects of the biology of aphelinid egg parasitoids of passionvine hopper (PVH) in New Zealand were measured. Centrodora scolypopae Valentine was common in Nelson and has probably dispersed throughout the range of PVH in New Zealand since last surveyed in 1962. Ablerus sp. has dispersed since its initial discovery in Auckland in 1985 and is now additionally found in the Waikato, the Bay of Plenty and Nelson. Ablerus sp. appears to be a thelytokous, multi-voltine primary parasitoid of PVH eggs, and not, as initially thought, a hyperparasitoid of C. scolypopae. Several biotic and abiotic factors that kill PVH eggs have been identified. Future studies to measure the impacts of egg parasitism on PVH populations will require careful sampling procedures that take into account spatial variation in PVH oviposition and parasitism within a site, and large seasonal variations in PVH populations that can be induced by weather and parasitism. Despite the wider distribution of C. scolypopae and the arrival of Ablerus sp., PVH continues to be a sporadic pest in many places.