A taxonomic study of the Erynia neoaphidis Remaudière & Hennebert (Zygomycetes: Entomophthoraceae) Group of insect pathogenic fungi, together with a description of the new speceies Erynia kondoiensis

Twenty-six isolates, including that derived from the type strain, of Erynia neoaphidis (syn. Entomophthora aphidis) were compared with nine isolates of the new species Erynia kondoiensis and with isolates of the closely related aphid pathogens Erynia nouryi and Erynia delphacis. Characters studied were primary spore size, in vitro growth rates, pathogenicity for two species of aphid, total fatty acid composition of mycelium and spores, and electrophoretic mobilities of their isoenzymes. All four species were distinct, with biochemical characters providing the clearest separation. Very little intraspecific variation was found within E. neoaphidis but one isolate of E. kondoiensis was quite distinct from the others by electrophoretic analysis. Morphologically, E. kondoiensis is very similar to E. neoaphidis but has smaller primary spores and the mycelium contains a much higher proportion of C 12:0 fatty acid. E. kondoiensis causes epizootics in Acyrthosiphon kondoi populations in Australia but is rarely found in the sympatric A. pisum. In contrast, E. neoaphidis very frequently infects A. pisum.