Trichomycetes (Harpellales) of New Zealand Austrosimulium larvae (Diptera: Simuliidae)

Summary

Three species of Trichomycetes were found in New Zealand Austrosimulium (Austrosimulium) Tonnoir larvae; Harpella melusinae Léger & Duboscq, Smittium sp. and an unidentified genistellacean. All three are new Southern Hemisphere records. The commonest species, H. melusinae, was found in seven species of Austrosimulium being particularly abundant in A. (A.) tillyardianum Dumbleton. In a sample of A. (A.) tillyardianum examined from the Wainui Valley Stream, Canterbury, it was found that H. melusinae was able to infect and produce trichospores in second instar larvae, and that the number of thalli and trichospores per larva increased in each subsequent instar.