Pathology of Coelomomyces stegomyiae in larval Aedes aegypti

Abstract

Fungi in the genus Coelomomyces infect mosquito larvae and develop within the larval hemocoel. Larvae usually die in the fourth and final instar, by which time, little of the larval fat body remains. To examine this pathology, Aedes aegypti larvae infected with Coelomomyces stegomyiae were chemically fixed, embedded in epoxy and sectioned for light microscopy. While C. stegomyiae directly invaded only cuticular epithelial cells, a number of other tissues were also affected. Hyphae ramified throughout the fat body in the lymphatic spaces between trophocytes leading to cell lysis and the depletion of the fat body. Hyphae also developed within muscle and gut tissues and in the lumen of hemopoietic organs and imaginal disks.

Key Words:

• Blastocladiales
• Chytridiomycetes
• Culicidae
• Diptera
• insect pathology
• mosquito