Sheehan W., F. L. Waekers, and W. J. Lewis. 1992. Discrimination of Previously Searched, Host-Free Sites by Microplitis croceipes (Hymenoptera: Braconidae). J. INSECT BEHAVIOR. 6: 323-331.

ABSTRACT

The ability offree-ranging parasitoids to discriminate between previously visited
and unvisited sites containing host kairomone (caterpillar frass) but not hosts
was tested. Females of Microplitis croceipes, a host specialist and plant gen-
eralist larval parasitoid of Helicoverpa (Heliothis) zea, were allowed to.fly freely
in a simulated plant patch in a~ight chamber. Wasps spent less time searching
frass sites previously searched by themselves or by conspecifics than unsearched
frass sites. In addition to chemical marking, spatial memory of visual cues was
implicated as a mechanism for discriminating against self-visited, host-free sites.