Trichomycetes occurring in both lentic (lake) and lotic (stream) habitats within the Halifax Regional Municipality, Nova Scotia, Canada

Abstract

Trichomycetes are an ecological group of fungi and protists found inside the gut lumen of aquatic insect larvae and have been reported virtually everywhere trichomycetologists have looked for them. Trichomycetes are common in freshwater aquatic habitats, both lentic and lotic, though lentic habitats have been explored less frequently. An inventory of trichomycetes inhabiting both stream (lotic) and lake (lentic) habitats was conducted within the Halifax Regional Municipality, Nova Scotia, Canada, including one site at the interface where a stream emptied into a lake. Twenty-six species of trichomycetes were collected from both lotic and lentic sites, nine of which are new species, all isolated from midge (Chironomidae) larvae. These are as follows: Smittium adaiosporum sp. nov. R.T. William and Strongman, Smittium cryptancora sp. nov. R.T. William and Strongman , Smittium petilum sp. nov. R.T. William and Strongman, Smittium peculiare sp. nov. R.T. William and Strongman, Stachylina abundans sp. nov. R.T. William and Strongman, Stachylina extensiva sp. nov. R.T. William and Strongman, Stachylina infrequens sp. nov. R.T. William and Strongman, Stachylina somnisimilis sp. nov. R.T. William and Strongman, and Stachylina uranus sp. nov. R.T. William and Strongman. In addition, a new continental record for Smittium hecatei L.G. Valle & Santam. previously reported from Spain and new regional geographic records for Smittium minutisporum Lichtw., Siri & M.M. White and Smittium mucronatum Manier & Mathiez ex Manier are documented. In addition, 14 other trichomycetes previously reported from Atlantic Canada were recorded and these included both harpellid fungi and protists in the genus Paramoebidium. Insects from the orders Diptera, Ephemeroptera, and Plecoptera were all found to contain trichomycetes. Data on the frequency of occurrence and the habitat preference for some gut fungi are discussed.