Habit: Perennial herb, floating in dense mats, rooted in mud when stranded; monoecious.
Stem: stolons floating or suspended in water.
Leaf: basal, emergent or floating, petioled; floating with swollen spongy cells abaxially.
Inflorescence: cyme, peduncle 0 or short.
Flower: unisexual, emergent, pedicelled; petals green-white to yellow.
Staminate Flower: filaments fused at least 1/2, anthers elongate.
Pistillate Flower: ovary chambers 1, styles 3--9, 2-lobed +- to base.
Fruit: fleshy berry, ellipsoid to spheric, smooth to ridged, dehiscing irregularly.
Seed: ellipsoid, spiny.
Species In Genus: 2 species: America.
Etymology: (Greek: living in pools)
Jepson eFlora Author: Robert F. Thorne, C. Barre Hellquist & Robert R. Haynes
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)
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