Immature stages of the bee fly Ligyra satyrus (F.) (Diptera : Bombyliidae): A hyperparasitoid of canegrubs (Coleoptera : Scarabaeidae)

We describe the third- and fourth-instar larva, pupa and biology of the hyp erparasitoid bee fly Ligyra satyrus (Fabricius). The larval and pupal morph ology of the bee fly is typical for members of the subfamily Anthracinae. T he bee fly larvae are found inside cocoons of the scoliid Campsomeris tasma niensis Saussure, an external parasite of canegrubs (Coleoptera: Scarabaeid ae) in sugarcane fields at Ayr and Bundaberg, Queensland. Ligyra satyrus ha s been recorded attacking only C. tasmaniensis. Ligyra and its relatives ar e all parasites of predatory and parasitic, ground-nesting aculeate Hymenop tera such as Sphecidae, Pompilidae, Tiphiidae and Scoliidae. Larval morphol ogy of the hyperparasite is similar to other ectoparasitic Bombyliidae and pupal morphology is compared to that of species in the same and related sub families. Rates of hyperparasitism at Gordonvale reported in the early 1900 s are relatively high, but our results show that currently they are very lo w at Ayr and Bundaberg. These results suggest that the impact of the bee fl y on natural control of the canegrubs by scoliids varies considerably.