The Insect Pathogenic Fungus Culicinomyces in Mosquitoes and Other Hosts.

Abstract

Experiments to define the host range of Culicinomyces, a fungus pathogenic to mosquito larvae, indicate that it may be restricted to aquatic larvae of certain families of the Order Diptera. Larvae of the families Culicidae (mosquitoes), Chironomidae (midges) and Ceratopogonidae (biting midges) are susceptible and the course of infection is the same in each. A species of the nematocerous family Psychodidae (moth flies) was insusceptible, as the cellular defence reaction restricted the infection to the invasion site. Several other aquatic insect larvae, as well as atyid shrimps and the mosquito-predaceous fish Gambusia, appeared to be unaffected after prolonged exposure to viable inoculum. The ceratopogonid species had no observable reaction to the pathogen; the chironomid species reacted weakly, which suggests that they may be the normal hosts of Culicinomyces. Mosquitoes reacted strongly to the infection and may be unusual hosts.