A genus of annual and perennial, sometimes scrambling herbs or low shrubs in which the leaves are simple, alternate and opposite, and often succulent. The flowers are regular, bisexual, and usually yellow or green in colour. The 5–8 sepals are fused and often attached to the ovary. There are no petals, but sometimes the numerous stamens are petal-like. The ovary is superior, inferior, or half-inferior. The fruit is a juicy or leathery capsule enclosed in the hardened calyx tube. There are 50–60 species, all restricted to the southern hemisphere.
Subjects: Plant Sciences and Forestry.