Description

Key Characters:

Growth Form: Plants annual or perennial, emersed, floating-leaved, or rarely submersed, glabrous to stellate-pubescent.

Stems: Rhizomes present or absent, stolons absent, corms absent, tubers absent.

Roots: Roots not septate.

Leaves: Leaves simple. Spirally arranged. Blades linear to lanceolate to ovate. Apex obtuse to acute. Base attenuate to cordate. Blade with translucent markings as dots or lines present or absent. Margins entire or undulating. Sessile or petiolate; petioles triangular, rarely terete (cylindrical). Stipules absent.

Flowers: Inflorescences racemes or panicles, rarely umbels, of 1–18 whorls, erect or decumbent, emersed; bracts coarse, apex obtuse to acute, surfaces smooth or papillose along veins, apex obtuse to acute. Flowers bisexual, subsessile to pedicellate; bracts subtending pedicels, subulate to lanceolate, shorter than to longer than pedicels, apex obtuse to acute; pedicels ascending to recurved; receptacle convex. Sepals 3, recurved to spreading, herbaceous to leathery, sculpturing absent. Petals 3, white, entire. Stamens 9–25; filaments linear, glabrous. Ovary superior, pistils 15–250 or more, spirally arranged on convex receptacle, forming head, distinct; ovules 1; style terminal or lateral.

Fruit: Fruits plump; often longitudinally ribbed; sometimes flattened; rarely abaxially keeled; abaxial wings absent; lateral wings absent; glands often present. Seeds with a U-shaped embryo; endosperm absent.

Ploidy:

Habitat:

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