PONTEDERIACEAE (Pickerel Weed Family)

(Alexander, 1937; Rosatti, 1987)

Plants annual or perennial. Stems glabrous, short to elongate. Rhizomes sometimes present. Leaves alternate or nearly whorled, glabrous, the petioles usually sheathing the stems, sometimes inflated or absent. Stipules papery to filmy or absent. Inflorescences various, sometimes reduced to a single flower, partially surrounded by a sheathing bract (spathe). Flowers perfect, zygomorphic or less commonly actinomorphic. Perianth of 6 petal‑like tepals, these usually fused basally. Stamens 3 or 6, sometimes dimorphic, the filaments fused to the perianth tube. Staminodes sometimes present. Ovary 1 per flower, superior, with 3 locules (2 locules sometimes reduced and sterile). Style 1 per flower, the stigma entire to 3‑lobed. Fruits capsules or utricles. About 8 genera, 30 species, nearly worldwide, mostly in tropical and subtropical regions. Submerged to emergent aquatics, sometimes floating.