Description
Key Characters:
Growth Form:
Minute to small, free–floating, glabrous, thalloid plants consisting of leafless, flat, disk-like or spheroid stems, often colonial and usually reproducing only vegetatively. fronds (thalloid shoots) fleshy or membranous, flat and subrotund to linear or thickened and nearly globose, sometimes 1–nerved to several–nerved, provided with 2 reproductive pouches, 1 marginal and the other on the upper surface, occasionally 1 on each margin near base, reproduction almost exclusively vegetative by budding in the marginal pouch or pouches, new plants sometimes remaining attached to the parent plant, eventually breaking away.
Stems:
Roots:
Leaves:
Leaves simple.
Usually opposite, sometimes alternate in upper half.
Blades linear to ovate, 0.5–4 cm long, 0.1–1.8 cm wide.
Surfaces glabrous to densely strigillose;, bluish green.
Margins serrulate to serrate with 1–6(–8) teeth on each side.
Subsessile.
Stipules absent.
Flowers:
Flowers in erect inflorescences.
Flowers bisexual (perfect), 4-merous.
Sepals keeled, 2.5–7.5 mm long, valvate, strigillose and often with glandular or nonglandular erect hairs.
Petals rose purple to white, 3.5–13.5 mm long; ovary ± densely strigillose, often also with glandular or nonglandular erect hairs.
Stamens 8, in two series; anthers versatile, dithecal, opening by longitudinal slits.
Ovary inferior, as many cells and carpels as sepals; ovules anatropous; style 1; stigma clavate or capitate, surrounded by or held above anthers at anthesis.
Fruit:
Capsules 3–7.5 cm long.
Seeds brown; obovoid; 0.7–1.1 mm long; papillose; the coma white; 5–8 mm long; readily breaking off.
Ploidy:
2n = 36
Habitat:
Open sites in wet forest to disturbed grassland; especially on open lava; in pastures; and along roadsides.
Elevation Range:
800–3,200 m.