Adults are less than four inches in total length, with females being slightly larger than males.

It has a fairly broad head, long legs and short tail. The ventral, or underside, color of adults is blackish maroon on the belly and gular area, with a buff-colored tail venter, or underside or abdominal area. The dorsum, or upper side, is blackish maroon with a suffusion of silver- to brass-colored shiny flecks that are interspersed with larger patches of metallic golden-orange. Young are black to dark brown and typically lack the brassy tint of adults. Species from this family breathe entirely through their thin moist skin, and have a unique tooth pattern, which is reflected in the science name for the family meaning, which means many teeth.

Not much is known about the reproductive cycle of desert slender salamander, but it is thought that courtship and breeding take place immediately after the first heavy rains of the winter, with egg laying occurring very shortly thereafter.

The desert slender salamander likely feeds on a variety of small arthropods that are found in moist, dark places.

The species primarily lives in moist subterranean spaces like porous soil, bedrock fractures, crevices under limestone sheets, talus, which is defined as a sloping mass of rock debris, above seeps and in animal burrows.