#microgastrinae

Copidosoma floridanum is an Encyrtid wasp whose brood is a fascinating example of polyembryony, in which multiple embryos form from a single egg. It is primarily a parasitoid of Noctuid moths in the subfamily Plusiinae. The Encyrtid egg will produce thousands of clone embryos. The mother C. floridanum will sometimes lay one male egg per host, or one female egg, or sometimes both. What's even more fascinating is that the wasp larvae have a caste system: the reproductives and the (precocious) soldiers. The reproductive larvae emerge during the caterpillar's last instar, consume it, and pupate into adult wasps. The soldiers emerge earlier, but never molt and die when the host dies. Their sole purpose is to protect their reproductive siblings from other parasitoid rivals and to kill their own opposite-sex precocious siblings. Since male soldiers compete for resources (caterpillar), by killing some of them off, the sterile soldiers are helping their genes survive by securing more resources for their clone reproductive siblings. In mixed-sex broods, the male larvae will try to hide and encyst themselves in the caterpillar's fat body to escape their murderous sterile sisters. Copidosoma competes with Microgastrine species such as Microplitis demolitor and Glyptapanteles pallipes. C. floridanum demonstrates haplodiploidy where unfertilized eggs become haploid males and fertilized eggs become diploid females. There are both male and female soldiers, but male soldiers tend to be less aggressive towards competitors. However, C. floridanum isn't invincible. There is one competitor, Trichogramma, that is also an egg parasitoid, and only uses the eggs of the moths. The adult wasps emerge long before the caterpillars hatch. When Trichogramma and Copidosoma end up in the same egg, the former usually ends up victorious.

A giant Cotesia (Braconidae) would be any hornworm's nightmare!