Recent phylogeographic work on Taricha torosa has revealed that the subspecific lineages, T. t. torosa and T. t. sierrae, are distinct evolutionary lineages that form a secondary contact zone in the southern Sierra Nevada of California. I examined the dynamics of this contact zone using two allozyme markers, mitochondrial DNA, morphometrics (head shape), and head color pattern. The subspecific lineages interbreed where they meet, and form a hybrid zone centered along the Kaweah River in Tulare County. Clines among genetic markers had similar shapes and centers, and ranged from 7–10 km wide. There is evidence of selection against hybrid genotypes in the center of the hybrid zone. Analyses of head shape and color pattern show that the two subspecies are phenotypically differentiated, and that patterns of differentiation in these characters are congruent with the genetic clines. The two subspecies constitute distinct evolutionary lineages and merit recognition as separate species: T. torosa (California newt) and T. sierrae (Sierra newt).