TWO SPECIES OF FUNGUS INFECTING THE EUROPEAN SKIPPER THYMELICUS LINEOLA (LEPIDOPTERA: HESPERIIDAE) IN QUÉBEC

Abstract

Since its initial introduction into North America (Saunders 1916) the European skipper Thymelicus lineola (Ochs.) has been found attacking timothy grass throughout much of eastern Canada and the United States reaching pest status in Ontario (Arthur 1966), Prince Edward Island (Thompson 1977), and Quebec (Doyle and Richard 1971; McNeil et al. 1975). Bucher and Arthur (1961) examined skipper larvae, collected near Princeville, Ontario, for naturally occurring pathogens and reported the presence of a nuclear polyhedrosis virus, a cytoplasmic polyhedrosis gut virus, and a spore forming bacterium. They stated that such pathogens represented a possible means of biological control if the skipper became economically important. An epizootic caused by an NPV in dense skipper populations near Normandin, Quebec (Smirnoff 1974), led to a series of experiments evaluating its efficacy as a microbial insecticide (Smirnoff et al. 1976; Duchesne 1980), its long term impact on the population dynamics of T. lineola (Duchesne 1980), and its possible effects on non-target organisms (Smirnoff et al. 1979).