GENETIC RELATIONSHIPS AMONG CHORISTONEURA SPECIES (LEPIDOPTERA: TORTRICIDAE) IN NORTH AMERICA AS REVEALED BY ISOZYME STUDIES
AbstractAllozymes at several polymorphic loci were assayed in larval collections of 12 recognized species and two possible new species of Choristoneura and two species of Archips. Most of the 48 collections came from high density populations, and those of C. fumiferana, C. occidentalis, and C. pinus represented much of the geographic range of these species. Mean percentage heterozygosity ranged from 2.0 to 18.6%, based on nine polymorphic loci. Three loci are sex-linked in C. fumiferana, two in C. pinus and C. occidentalis and probably in some other members of the group. Allozymes of aspartate transaminase (AAT-1) were most varied among the species and permit identification of individual C. fumiferana in better than 95% of cases. Among the group of coniferophagous Choristoneura species genetic distances were small (max. Nei = 0.232); C. fumiferana was the most distinct species. Wagner trees based on modified Rogers’ distances supported the above conclusions but indicated that separations among C. biennis, C. orae, C. occidentalis, C. carnana, C. subretiniana, and the two new species of Choristoneura were very small and probably below the species level, based on the allozymes measured.