Droseraceae
Content
Description
Annual or perennial insectivorous herbs. Roots adventitious (some extra-neotropical species with tubers). Stems 0.1-30 cm, aerial (subterranean in some extra-neotropical species). Leaves generally stipulate, alternate, simple (variously lobed or peltate in some extra-neotropical species), covered with glandular hairs; stipules intrapetiolar (lateral or absent in some extra-Guianan species); petiole grading into blade or well defined, hairy or glabrous; blade membranaceous, linear to circular, margin covered with glandular hairs. Inflorescences terminal, rarely lateral, unbranched, one-sided or dichasial cymes, sometimes flowers solitary; peduncle slender, up to 20 cm long, with glandular hairs, non-glandular hairs or glabrous (also in bracts, pedicels and sepals); bracts minute, green, red or scarious; pedicels present. Flowers generally 5-merous, actinomorphic (zygomorphic in some extra-tropical species), hermaphrodite; sepals joined at base or free; petals free, white or pink, rarely yellow, membranaceous, spathulate or obovate, usually persistent; stamens generally 5, filaments filiform, terete, anthers usually bilocular; pollen generally released in tetrads, generally spinulose; ovary superior, glabrous, carpels generally 3, united, placentation parietal, styles 3-5, usually partite at base or unbranched, rarely united, often further dividing distally, stigmas tapered or swollen, often papillose. Fruits dehiscent (rarely indehiscent in extra-Neotropical species), papery capsules; seeds numerous (few in some extra-Neotropical species), embryo embedded in copious endosperm, rich in starch, oil and protein, cotyledons minute.
Distribution
Australasia, Cosmopolitan present, Neotropics present
Cosmopolitan with centre of diversity in Australia, 4 genera and ca. 120 species, the genus Drosera is the only one in the Neotropics.