Distribution of Epichloë Typhina (Ascomycetes) and Its Parasitic Fly

SUMMARY

Fresh and dried stromata of Epichloë typhina, the cause of choke disease of grasses, were examined for infections by a host-specific fly, Phorbia phrenione. Over 35% of 4,685 stromata from 17 countries growing on about 50 species of grass were parasitized by the fly. The insect does not depend on a particular grass species, but it occurs wherever the fungus is found. The distribution of E. typhina with P. phrenione appears to be restricted to the Northern Hemisphere and ranges from East Asia, throughout Europe and North America including Mexico. The discovery of parasitized stromata in E. cinerea indicates that similar parasitic relationships may exist between other members of the genus Epichloë and insects. The life cycle of E. typhina and the hyperparasitic fly are briefly described.