Stems erect to prostrate, usually rooting nodally, glabrous or strigose. Roots not thickened basally, glabrous. Proximal cauline leaf blades ovate to broadly ovate, 0.8-2.7 × 0.8-1.9 cm, base rounded to weakly cordate, margins entire or dentate, apex rounded or obtuse. Inflorescences: bracts lanceolate to oblanceolate or sometimes ovate. Flowers: receptacle glabrous; sepals 5, spreading or reflexed from base, 1.5-3 × 1-2 mm, glabrous; petals 5-6, 3-5 × 1-2 mm; nectary scales glabrous. Heads of achenes hemispheric or globose, 2-4 × 3-4 mm; achenes 1.2-1.4 × 1-1.2 mm, glabrous; beak lanceolate to lance-filiform, straight or curved, 0.4-1 mm.
Phenology: Flowering late spring–summer (Jun–Aug).
Habitat: Wet soil or shallow water, in marshes and edges of streams and lakes
Elevation: 2000-2900 m
Ariz., Calif., N.Mex., Mexico, Central America (in Guatemala).