Histopathological effects of diflubenzuron on the cirripede crustacean, Balanus eburneus

Histopathological studies on the cirripede crustacean, Balanus eburneus, at light and electron microscopic levels indicated that the chitin-inhibiting insecticide, diflubenzuron, caused similar disruption of the exoskeleton as observed in insects. Under the light microscope, globular particles were present within the chitinous layers of the cuticle, and these particles appeared electron dense and pleomorphic at the ultrastructural level. The cytoplasm of the cuticle-secreting epidermal cells appeared more dense and showed at least a five-fold increase in multivesicular bodies, which possessed electron dense cores. Barnacles exposed to diflubenzuron for 10 days or longer at 750 and 1,000 ppb were delayed in the premolt phase of cuticle secretion.