The endocrine basis for developmentally stationary prepupae in larvae ofTrichoplusia ni pseudoparasitized byChelonus insularis

Summary Larvae of the cabbage looper,Trichoplusia ni, precociously initiate metamorphosis in the penultimate instar when parasitized byChelonus insularis. Some larvae developing from stung eggs precociously spin cocoons, but upon dissection contain no live or obvious parasites. Such pseudoparasitized larvae greatly slow down in development as prepupae, due to a suppressed ecdysteroid titer which in turn may be caused by a suppressed juvenile hormone titer.Abbreviations JH juvenile hormone - JHA juvenile hormone analog - JHE juvenile hormone esterase