Description from Flora of China
Shrubs or small trees; branches often terminating as spines. Leaves opposite or subopposite, sometimes crowded on short lateral shoots, simple, entire, estipulate. Flowers solitary, terminal or 1-5 in axillary or terminal clusters, actinomorphic, bisexual. Floral tube thick, leathery, adnate to ovary and produced above it; sepals thick, valvate, persistent. Petals showy, red [or white], strongly crumpled. Stamens numerous, covering inner surface of floral tube from rim to ovary. Ovary inferior, multiloculed; style exserted; stigma capitate. Fruit berrylike, with leathery rind, retaining a crown of sepals. Seeds many, with translucent, juicy sarcotesta; cotyledons spirally rolled.
Two species: one endemic to the Indian Ocean island of Socotra; one of uncertain native origin, probably from C and SW Asia, now widespread in cultivation.
(Authors: Qin Haining (覃海宁); Shirley Graham)