Radsia nigrovirescens, the brooding chiton, is a small polyplacophoran mollusc in the family Chitonidae,[1] found on the west coast of southern Africa.

The valves of the shell are dark brown to black and bear indistinct radiating ridges.

The girdle is of a rufous color and has a black band; it is covered with large, smooth scales that may have a coppery sheen.

The species forms tightly packed groups that can be found under stones below the inter-tidal zone.

[2] The species derives its common name from the unusual adaptation of brooding its eggs under its girdle, protecting them until they develop into fully formed baby chitons.