Anomalous Development of the Cuticle of Mosquitoes Induced by Griseofulvin

Abstract

Griseofulvin is an antibiotic that purportedly interferes with the biosynthesis of cell-walls of fungi which contain chitin. The rearing of larvae of Aedes atropalpus, Coquillett in a medium containing griscofulvin resulted in (a) the occurrence of gross anatomical changes in the cuticle, (b) the detachment of somatic muscles from the integument, and (c) a prolongation of the molting cycle. With the exception of the last-mentioned effect, all modifications became apparent during an instar subsequent to the one initially exposed to the compound. The detachment of muscles from the integument apparently is caused by the anomalous development of the cuticle and not that of the muscles. The effect of griseofulvin on the development of A. alropalpus was shown to be related directly to the molting cycle. The critical period for inducing given anomalies during a molting cycle was determined. The mode of action of griseofulvin is unique in comparison to those of conventional insecticides.