ASIAN GYPSY MOTHS (LEPIDOPTERA, LYMANTRIIDAE) IN NORTH-AMERICA - EVIDENCE FROM MOLECULAR-DATA

Gypsy moths, Lymantria dispar L., were accidentally introduced into th e United States from Europe more than a century ago and have become a major forest pest in eastern North America. Recently, concern has aris en over possible establishment of gypsy moths of Asian origin in weste rn North America. Because Asian moths have distinctive ecological and behavioral characteristics, it is essential to monitor their presence. Identification of pheromone-trapped males based on morphology is not straightforward, but comparisons of mitochondrial DNA (mtDNA) restrict ion fragment length polymorphisms (RFLPs) and sequences reveal diagnos tic differences between Asian and North American haplotypes. An mtDNA survey of moths trapped in the Pacific Northwest in 1990 and.1991 docu ments the presence of moths of Asian origin at several sites in North America. These results provided the basis for undertaking efforts in 1 992 to eradicate gypsy moth populations of Asian origin in both the Un ited States and Canada: