Trichomycetes are commensalistic fungi that live obligately in the guts of various insects, crustaceans, and millipedes. The variety of host and habitats, the worldwide occurrence of all families, and the intercontinental distribution of some genera of these fungi indicate that the relationship with arthropods is very ancient. Dr. Robert Lichtwardt of the University of Kansas seeks to understand how and when trichomycetes evolved and became geographically distributed with their arthropod hosts. Data from Australia and New Zealand suggest that some fungal taxa may have had common ancestors on Gondwana at least 70-80 million years ago. Evidence to support the Gondwanan origin of austral trichomycetes will be sought in southern South America. Studies of other gut fungi in marine, terrestrial, and freshwater arthropods may provide evidence of how long certain species have been radiating with their hosts, and the roles of dispersal and vicariance in allopatric distributions. Phylogenetic analysis of trichomycete genera will assist in understanding their evolution and biogeography, and isozyme phenotypes of cultured isolates from different geographical regions of the world will provide some information on species variability. Harpellales, whose species grow only in larval stages of aquatic insects, will be studied to see whether or not their propagules can disperse phoretically with adults.
