Aquatic herbs, floating or submerged with creeping rootstock; stems dichotomously branched, slender, compressed, fleshy; leaves submerged or floating, distichous, sessile, half amplexicaul, narrow, linear-oblong, margins crisped, finely serrulate, 3-nerved; stipules small, obtuse, caducous; spikes few flowered, peduncles erect, long, ascending or curved, tapering upwards; spathe erect, membranous; flowers green, small, ebracteate; perianth segments-4, suborbicular, concave, valvate; stamens with sessile anthers-4, didymous, slits extrorse; carpels-4, sessile, 1-celled, 1-ovuled, stigma subsessile, persistent; drupelets small, obliquely ovoid, long beaked tapering upwards, coriaceous or spongy, compressed, ribbed; seeds solitary, subreniform.