in C. F. P. von Martius et al., Fl. Brasil. 2(1): 90. 1842.

Etymology: Greek oxys, sharp, and carya, nut
Treatment appears in FNA Volume 23. Treatment on page 140. Mentioned on page 8.

Herbs, perennial, not cespitose, stoloniferous, aquatic. Culms solitary, trigonous. Leaves basal; ligules present, ciliate; blades flat to V-shaped in cross section, prominently keeled on abaxial surface. Inflorescences terminal, umbellate heads or capitate; involucral bracts 1–6+, spreading, leaflike. Spikelets: scales 5–10+, 3-ranked, spirally arranged, each subtending flower. Flowers bisexual; perianth absent; stamens 3; styles 2-fid, linear, base persistent. Achenes plano-convex, margins and apex corky.


Tropical and subtropical America and Africa.


Species 1.

Lower Taxa