Perennials, rhizomatous; dioecious or sometimes androdioecious. Leaf blades hard, linear to subulate-involute; ligule a line of hairs. Inflorescence terminal, compound, composed of many single racemes subtended by prophylls and spathate sheaths and condensed into a compact fascicle. Staminate inflorescence with exserted racemes bearing several spikelets and ending in a short point. Female or bisexual inflorescence stellately globose, falling entire, composed of numerous racemes reduced to a single basal spikelet hidden among subtending spathes, its rachis prolonged into a long needle-like spine. Spikelets dorsally compressed, staminate spikelets herbaceous, female spikelets papery. Staminate spikelet with shorter glumes and both florets staminate. Female spikelet with glumes equal to spikelet and lower floret sometimes paleate and staminate. Upper lemma in both slightly indurate with flat hyaline margins. x = 9.

Four species: seashores from India to Japan, SE Asia, and Australia; one species in China.

(Authors: Chen Shouliang (陈守良); Sylvia M. Phillips)