Single plant on sand dunes. Growth habit, caespitose (not stoloniferous), leaves broad (up to 20 mm wide), bright grass green (concolorous), leaf bases bright green.

Growing with Ficinia nodosa, Melilotus indicus, Sporobolus africanus and Lagurus ovatus in fine basalt sand.

To date I have only seen this species on Rangitoto Island - I have yet to see any definite specimens of D. nigra - widely reported for the island.