Plants semi-aquatic, stoloniferous annuals or short-lived perennials. Culms erect or decumbent and rooting at the lower nodes, up to 150 cm tall, with many nodes. Blades 10-20 cm long, 4-8 mm wide, widely divergin, glaucous, scabrous, acuminate. Panicles 15-30 cm long, narrow, with numerous spikelike flexuous branches racemosely arranged on the central axes; branches 3-10 cm long, purple. Spikelets narrowly oblong, 1-1.7 mm long, broadly obtuse or emarginate and minutely mucronate; lemmas elliptic-oblong, 1-5-2 mm long, scabriulous, shortly pilose on the veins, obtuse. Caryopses chestnut brown, narrowly obovate, btusely trigonous in cross-sectioin.
Dinebra coerulescens grows on sandy river banks adin shallow ater, forming stands, at 650-800 m, in Ethiopia, Senegal, Zaire, Angola, and Zambia. It is also a weed of rice in Costa Rica.
Dinebra coerulescens is widespread in western Africa but is replaced by the semi-aquatic Dinebra chinensis from northern Kenya southwards to Natal. That species differs from Dinebra coerulescens in not being stoloniferous and in having smaller lemmas (0.8-1.4 mm long.