Perennial forb to 1.5m tall, aquatic or in mud. Emergent leaves usually in whorls of 3-4, 0.3-0.9cm long, to 3mm wide, flat, glaucous green to reddish purple, lower leaves deeply lobed, upper leaves entire. Submerged leaves in whorls of 3-4, feathery, 0.4-1.2cm long, with 8-20 leaflets. Male and female flowers on the same plant, occasional flowers bisexual, usually small (less than 3mm across). Male flowers with 4 small hooded yellow petals, which fall off easily. Female flowers with 0 petals, and white stigmas. Flowers solitary at the bases of the leaves.
Description and photo in G.M. Cunningham, WE Mulham, PL Milthorpe and J H Leigh (1981 and later printings) Plants of Western New South Wales pages 538-9