Aerva

Perennial herbs (sometimes flowering in first year), prostrate to erect or scandent. Leaves opposite or alternate, entire, flat. Inflorescences axillary and terminal, sessile or pedunculate, woolly spikes, or spikes arranged in a loose panicle, bracteate. Flowers unisexual or bisexual, plants probably sometimes polygamous, solitary in axils of bracts; bracteoles 2; bracteoles and perianth falling together with fruit but bracts and bracteoles persistent. Tepals 5, free, oval, or lanceolate-oblong, sometimes unequal, some or all softly woolly, with membranous margin and a thin to wider green centre. Stamens (and subulate staminodes of female flowers) 5; filaments connate at base into a basin or cup, alternating with subulate to oblong pseudostaminodes; anthers 2-thecous. Ovary small; ovule solitary, suspended from an elongated basal funicle; style shorter or longer than ovary; stigmas 2 or capitellate. Capsule thin-wall, delicate, bursting irregularly, membranous, enclosed in perianth. Seed compressed-reniform, firm, black. x= 7, 8, 9, 10, 11 (polyploidy) .