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Dr. Merlin White


Trichomycetes, a former class of obligate endosymbiotic fungi, are now recognized as an ecological group that inhabits the gut(s) of immature insects. Though the biodiversity and geographical distribution of trichomycetes are worldwide, our knowledge of the group in the Pacific Northwest is limited due to the few researchers conducting studies on them. Dry Creek drainage in Boise, Idaho was selected in the winter of 2009-10 as a potential site to find gut fungi. This initial survey provides the first account of Ephemerellomyces aquilonius, a species previously documented and studied only in Norway. Ephemerellomyces aquilonius (a monotypic genus) is a member of the Harpellales, an order of trichomycetes, and was dissected from the digestive tracts of mayflies (Ephemeroptera) collected from the creek. Amongst the various aquatic habitats surveyed and hosts recovered, gut fungi were also documented in stoneflies (Plecoptera) and black flies (Diptera: Simuliidae). Our investigation provides a significant new record of the very rare and unusual taxon, E. aquilonius, previously only known in Western Europe. The success of this brief survey demonstrates promise for further discoveries of gut fungi at this site, in Idaho and the Pacific Northwest. This disjunct distribution bridges an enormous geographical divide, although the species actually may be more widespread than earlier anticipated. Future collections and research on specimens from Dry Creek, with sequence data to be generated in our laboratory will be eagerly awaited as we place this unusual species in our expanding molecular-based phylogenies. We highlight here the morphology of E. aquilonius and some of the other endosymbionts found there.