Larva slender with low tail fin, long gill branches, dark flecks on the anterior third of throat, and broad pale stripe down back. Near cool streams and spring seeps in forests of dissected, rocky uplands and valley edges. Dark-sided subspecies partial to twilight zones of caves, sometimes deep within caves and along surface streams nearby. They are sometimes seen on tree trunks, damp leaves, rock faces, or even on roads during these forays. Eggs laid in wet underground crevices in late summer or autumn.
Hatchlings appear in late winter or early spring and larvae transform in summer.