The World Flora Online

SELECTED REFERENCES Davis, C. C. and M. W. Chase. 2004. Elatinaceae are sister to Malpighiaceae; Peridiscaceae belong to Saxifragales. Amer. J. Bot. 91: 262–273. Tucker, G. C. 1986. The genera of Elatinaceae in the southeastern United States. J. Arnold Arbor. 67: 471–483.

Herbs [subshrubs], annual [short-lived perennial], synoecious [polygamous]. Leaves opposite [whorled], simple; stipules present; petiole present or absent; blade margins entire or serrulate; venation pinnate. Inflorescences axillary, usually cymes or flowers solitary, sometimes 2[–3]-flowered clusters. Flowers bisexual [pistillate]; perianth and androecium hypogynous; hypanthium absent; sepals 2–5, distinct or connate basally; petals (0 or) 2–5, distinct; nectary absent; stamens [0–]1–10, distinct, free; anthers dehiscing by longitudinal slits; pistil 1, 2–5-carpellate, ovary superior, 2–5-locular, placentation axile; ovules 2–33[–44] per locule, anatropous; styles 2–5, distinct; stigmas 2–5, capitate. Fruits capsules, dehiscence septicidal or irregular. Seeds 2–33[–44] per locule.

Herbes'annuelles, parfois aquatiques, sous-arbrisseaux à arbrisseaux.'Feuilles'opposées ou verticillées, généralement dentées à dents glanduleuses, parfois entières; stipules interpétiolaires.'Inflorescences'en cymes ou fascicules axillaires ou fleurs solitaires axillaires; bractées parfois présentes.'Fleurs'pédicellées ou sessiles, petites, ☿, régulières; sépales 2-5(6), imbriqués, libres ou soudés à la base; pétales en même nombre que les sépales, imbriqués, libres, persistants; étamines en nombre double ou égal par avortement à celui des pétales; filets libres, souvent élargis-ailés à la base; anthères dorsifixes, versatiles, introrses, 2-loculaires, à loges souvent divergentes, déhiscentes par fentes longitudinales; ovaire supère, 2-5-loculaire, à placentation centrale; ovules ∞, horizontaux ou ascendants, anatropes; styles 2-5, libres; stigmates ± renflés.'Fruits': capsules septicides.'Graines sans albumen; embryon droit ou courbé.\n\t\t\tFamille des régions tropicales, subtropicales et tempérées, comprenant 2 genres et 35-40 espèces; au Congo, 1 genre et 1 espèce.

Fruit a septicidal capsule Ovary superior, 3–5-celled; placentation axile; styles 3–5, free; ovules numerous Stamens from as many to twice as many as the petals, free, hypogynous; anthers 2-celled, opening by longitudinal slits Petals as many, hypogynous, imbricate, persistent Seeds without endosperm, straight or curved; embryo with short cotyledons Herbs or low shrubs Leaves opposite or verticillate, simple; stipules present, paired Flowers small, actinomorphic, hermaphrodite, axillary, solitary or cymose Sepals 3–5, free, imbricate Ovary superior, 3–5-celled; placentation axile; styles 3–5, free; ovules numerous Stamens from as many to twice as many as the petals, free, hypogynous; anthers 2-celled, opening by longitudinal slits Petals as many, hypogynous, imbricate, persistent Seeds without endosperm, straight or curved; embryo with short cotyledons Herbs or low shrubs Leaves opposite or verticillate, simple; stipules present, paired Flowers small, actinomorphic, hermaphrodite, axillary, solitary or cymose Sepals 3–5, free, imbricate

Herbs or low shrubs Leaves opposite or verticillate, simple, entire or toothed; stipules present, paired Flowers small, actinomorphic, bisexual, axillary, solitary or in small cymes, fascicles or verticillate clusters Sepals 3–5, imbricate Seeds without endosperm, straight or curved; embryo with short cotyledons Fruit a septicidal capsule Ovary superior, 3–5-locular, multiovulate; styles 2–5, free Stamens as many, or twice as many as the sepals; anthers 2-thecous, opening by longitudinal slits Petals 3–5(6), imbricate, persistent Leaves opposite or verticillate, simple, entire or toothed; stipules present, paired Flowers small, actinomorphic, bisexual, axillary, solitary or in small cymes, fascicles or verticillate clusters Sepals 3–5, imbricate Seeds without endosperm, straight or curved; embryo with short cotyledons Fruit a septicidal capsule Ovary superior, 3–5-locular, multiovulate; styles 2–5, free Stamens as many, or twice as many as the sepals; anthers 2-thecous, opening by longitudinal slits Petals 3–5(6), imbricate, persistent

Fls regular, perfect, hypogynous, 2–5-merous, pet small, stamens in 1 or 2 series; ovary 2–5- locular, with axile or basal-axile placentas; styles 2–5; fr a many-seeded septifragal capsule; seeds without endosperm; herbs, mostly small, of wet soil or shallow water, with simple, opposite (or whorled), stipulate, entire or toothed lvs and small, axillary, solitary or cymose fls. 2/40, widespread.

Herbs annual, perennial, or subshrubs, semiaquatic or terrestrial, dwarf. Leaves opposite or verticillate, petiolate; stipules paired; leaf blade simple, margin entire or serrate. Flowers solitary, clustered, or in axillary cymes, bisexual, actinomorphic, small. Sepals 2-5, imbricate, free or slightly united, thinly membranous or with nearly pellucid margins. Petals 2-5, imbricate in bud, free, membranous. Stamens 1 or 2 × as many as sepals, free; anthers dorsifixed, 2-loculed. Ovary superior, 2-5-loculed, many ovuled; placentation axile; styles 2-5, free, short; stigmas capitate. Fruit a septicidal capsule, membranous, leathery, or crustaceous. Seeds numerous, straight or curved, small; testa often rugose; endosperm absent.

Fruit a septicidal capsule Seeds straight or curved, without or with very little endosperm; embryo straight or curved, with short cotyledons Ovary superior, (2–)3–5-locular, with axile placentation; ovules numerous; styles (2–)3–5, free Stamens as many as and alternate to twice as many as the petals, free, hypogynous; anthers dithecous, opening by longitudinal slits Petals (2–)3–5(–6), hypogynous, imbricate, persistent Sepals (2–)3–5(–6), free, imbricate, not nerved or 1-nerved, mostly with pellucid margins Herbs or small shrubs, sometimes aquatic Leaves opposite or verticillate, simple or submerged leaves sometimes much divided, entire or serrate; stipules present, paired Flowers small, regular, hermaphrodite, axillary, solitary, cymose, fasciculate or in glomerules, occasionally cleistogamous Seeds straight or curved, without or with very little endosperm; embryo straight or curved, with short cotyledons Ovary superior, (2–)3–5-locular, with axile placentation; ovules numerous; styles (2–)3–5, free Stamens as many as and alternate to twice as many as the petals, free, hypogynous; anthers dithecous, opening by longitudinal slits Petals (2–)3–5(–6), hypogynous, imbricate, persistent Sepals (2–)3–5(–6), free, imbricate, not nerved or 1-nerved, mostly with pellucid margins Herbs or small shrubs, sometimes aquatic Leaves opposite or verticillate, simple or submerged leaves sometimes much divided, entire or serrate; stipules present, paired Flowers small, regular, hermaphrodite, axillary, solitary, cymose, fasciculate or in glomerules, occasionally cleistogamous