The serpent-skinned brittle star has a flat, disc-like body with file long, spindly arms extending outward from the edge of the disc. The texture of its body is granular, which is an important identification characteristic as it is not always the dark black-brown colour usually seen.
These arms are thin and fragile, but highly mobile and flexible. The arms are segmented with tiny armour plated protecting each joint. The sides of each arm are protected by rows of short spines, folded close to the arm. Rarely, these arms are banded, but they are more commonly solid black-brown like the central body.
At the base of each arm are two slits which lead into chambers where the brittle star's eggs can be fertilised. The young are brooded in these chambers and emerge as fully formed, but tiny, adults. Unlike many other brittle stars, the serpent-skinned brittle star has no free-swimming planktonic phase.
This brittle star lives in large groups, often with thousands of individuals, on gravel and sandy surfaces on the South African coast, from the Cape to southern Namibia.