| Laboratory-reared mosquitoes (Aedes aegypti L.) and black flies (Simulium vittatum Zetterstedt) were used to investigate development and morphology of the trichomycete fungus Smittium culisetae Lichtwardt. The development of Sm. culisetae differed among three temperatures; mosquito larvae had the most trichospores at 17°C, while black fly larvae had the most at 30°C. Morphology of Sm. culisetae also differed between the two hosts, with Sm. culisetae being significantly larger in mosquito hosts than in black fly hosts. In addition, fixation of S. vittatum in ethanol, in some cases, altered the morphology of trichomycetes but to what degree remains to be investigated. Under stressed conditions such as starvation of the mosquito larvae, Sm. culisetae did not produce trichospores. However, Sm. culisetae thalli sporulated when they were expelled from the host gut, and these trichospores were able to inhabit the new host. This is the first report of trichomycete sporulation outside the host. In addition, the distribution of three Smitlium spp. in the mosquito host was investigated. When more then one species of trichomycete was present, there was a shift of thalli from their usual location in the rectum to the posterior region of the intestine of the mosquito hindgut. |
