Studies of Parasite Oviposition Behaviour.: II. Leptomastix dactylopii Howard (Hymenoptera, Encyrtidae)

Abstract

Entomophagous insects as a group show all degrees of host preferences from the polyphagous species which develop on variable numbers of hosts to the stricdy monophagous forms wllich are limited to development on a single host species. Polyphagy is generally regarded as the more primitive condition while the fact that even amnng species so characterized there frequentIy exist strong preferences in the form of host determined races is taken as an indication of one method by which the more specialized habit was attained. The general problem of the dynamics of host selection in the entomophagous Hymenoptera and Diptera has attracted the attention of numerous investigators (eg. Thompson & Parker 1927, Salt 1935, Ullyett 1936) and many have stressed that for any given parasite the range of hosts attacked and developed on is the end result of various processes. These processes have been conveniently described by Salt (1938) as host finding, selection, and suitability, the first phase being more usually referred to as habitat selection (Flanders 1937, Thorpe 1945). This interpretation has received wide acceptance among biological control and allied workers.