It has a black body, broken yellow or orange irregular striping along its spine, and a tail fin well evolved for swimming.

Like other mole salamanders, it is found near pools or slow-moving streams and has a very secretive lifestyle, making it difficult to find.

The genetic relationship, however, is still unclear, as more evidence is needed from additional genes and individuals [3][4] In both species, eggs are laid singly near the water surface on rush-like spikes, but sometimes in small clusters at the base of logs or sticking to vegetation in the deeper parts of a pond.

[6] Hogan's study also noted the adverse effects of siltation occurring in Valencia Lagoon from the highway embankment erosion created by widening of Route 1; it was reasoned that the siltation should decrease once the vegetation became re-established on these slopes and allow the habitat to improve; moreover, the Earth Metrics study derived additional mitigation for the County of Santa Cruz to follow in considering any further discretionary actions around Valencia Lagoon.

[6] Most of this salamander's adult life is spent in upland coast live oak forest in small animal burrows during the long dry season (May to October) in coastal California.

Predators that eat long-toed salamander larvae include aquatic invertebrates, garter snakes, and other vertebrates.

A. m. croceum juveniles, though, often spend their first summer close to the breeding pond in a rodent burrow or rock fissure, only later migrating uphill into the forest.