Fungal symbionts (Harpellales) in Norwegian aquatic insect larvae

Abstract

Collections of aquatic insect larvae in Norway, over a 40 d period in May and Aug 2002, resulted in finding more than 25 species and one new genus of Harpellales (Trichomycetes). Nine new fungal symbionts are described and named: Ephemerellomyces aquilonius (a new monotypic genus), Glotzia stenospora and Legeriosimilis europaeus in mayfly nymphs (Ephemeroptera); Genistelloides amplispora and G. communis in stonefly nymphs (Plecoptera); and Smittium biforme, Sm. precipitiorum, Stachylina acutibasilaris and St. lentica in midge larvae (Diptera: Chironomidae). Two possibly new species of Smittium in Chironomidae larvae are described but not formally named. New hosts and biogeographical distributions are recorded for 14 previously described species, including the rare occurrence of Smittium simulii in mosquito larvae.

• biogeography
• Diptera
• Ephemeroptera
• gut fungi
• Plecoptera
• symbiosis
• Thaumaleidae
• Trichomycetes

We are indebted to the National Science Foundation for award DEB-0108110, which supported this research. We acknowledge with considerable appreciation a number of biologists in Norway whose assistance materially facilitated our research and made it more successful. Leif Ryvarden provided excellent laboratory space and facilities in the Department of Botany, University of Oslo. John E. Brittain, Trude Vrålstad and Arne Holst-Jensen suggested a number of collecting sites in the vicinity of Oslo. Arne Fjellheim, Stavanger Museum, allowed use of the subalpine Field Station at Ekse administered by the University of Bergen, and arranged, through Ole Kristian Berg, Zoologisk Institutt, University of Trondheim, our use of the Snåsavatnet Field Station in the northern part of Trondheimsfjord. We thank these entomologists for their considerable time and expertise in identifying larval hosts of Harpellales: John E. Brittain (Plecoptera and Ephemeroptera) and Jan Emil Raastad (Simuliidae), The Natural History Museums, University of Oslo; Ole A. Sæther (Chironomidae), Museum of Zoology, University of Bergen; and Brad Sinclair (Thaumaleidae), Museum Koenig. We thank Matías Cafaro who provided valuable comments on a draft of this manuscript. We also are grateful for the thoughtful comments of C. Eddie Beard and an anonymous reviewer that improved the paper.