Taxonomic status of male salamanders of the Ambystoma jeffersonianum complex from an Ontario population, with the first record of the Jefferson salamander, A. jeffersonianum (Green), from Canada

Abstract

Nine morphological criteria were used to determine the taxonomic status of the male salamanders of the Ambystoma jeffersonianum complex from a population near Streetsville, Toronto Township, Peel County, Ontario: (a) snout–vent length; (b) ratio of tail length to snout–vent length; (c) internarial width; (d) extent of separation or overlap of the toes of adpressed limbs; (e) total length; (f) ratio of tail length to total length; (g) ratio of internarial width to snout–vent length; (h) colouration of dorsal, lateral, and ventral body surfaces; and, (i) extent and distribution of the bluish spotting. The results indicate that all of these males resemble A. jeffersonianum or A. platineum rather than A. latérale. Since A. platineum males occur very rarely in nature, these Streetsville individuals are logically assigned to A. jeffersonianum. This represents the first record of this species from Canada. Based upon this new distributional datum of A. jeffersonianum and of the two Diploid species from the literature, we suggest that these triploid species may have originated in post-Wisconsin times and subsequently dispersed northward.