Shrubs or small trees, usually spiny; spines sometimes ending in short shoots. Leaves alternate, exstipulate. Flowers hermaphrodite in axillary, solitary or fascicled dichotomous cymes; sometimes on the spiny branchlets. Calyx 4-5-lobed. Petals 4-5, spreading. Stamens 4-5, inserted on the margin of the disc or slightly below it; filaments slender, broad. Disc broad, sinuate or lobed. Ovary sunk in the disc, 2-3-celled; ovules 2 in each cell; style short; stigmas 2-3. Capsule turbinate or rarely globose, 3-gonous, 2-3-valved, 1-4-seeded; seeds arillate.