In-Situ Development of Parasitoid Copidosoma floridanum in Caterpillar Host

Copidosoma floridanum is a parasitic wasp that injects its eggs into the eggs of its host, moths of the subfamily Plusiinae. As the wasps mature within their hosts, the embryos undergo polyembryonic development, in which the egg clones itself, forming a mass of identical embryos called the polygerm. These embryos differentiate into two types of larvae, soldier morphs and reproductive morphs, the latter of which consumes the host’s tissue before emerging from the host. Previous research has used dissection and microscopy techniques to observe the wasp’s larval activity, thus in situ procedures to observe this parasite-host interaction are understudied. Our aim is to investigate the position and orientation of the polygerm at various stages of the host’s development, as well as how the developing wasp larvae interact with specific host tissues. Histological images of these interactions will be analyzed between two closely related host species within the Plusiinae subfamily, Trichoplusia ni and Chrysodeixis includens. Comparing the location of the wasp embryos between them may reveal evolutionary differences in how the parasitic wasp interacts with each host species. This is also expected to lead to a preliminary collection of histological reference images for future research and literature regarding the parasitic wasp Copidosoma floridanum.