Pubescent shrubs or small trees with stellate hairs (with or without simple hairs) on branchlets, leaves and flowers. Leaves alternate, petiolate, penninerved, discolorous; stipules usually deciduous, free. Inflorescence of cymes arranged in panicles or racemes, rarely umbellate or flowers solitary. Flowers bisexual; sepals 5, usually falling before fruit development; petals 5 (rarely fewer) or absent; stamens free, or rarely, shortly adnate to the petal base, usually longer than petals (if present); disc absent, to conspicuous and forming a ring around the ovary summit; ovary inferior to superior, carpels 3, style 3-lobed. Fruit a schizocarp, splitting to release 3 woody mericarps that are usually operculate on the inner face; seed smooth, with a small basal aril.
About 65 species, largely restricted to Australia, with 8 in New Zealand.
In the following key and descriptions, the state of the ovary (inferior/superior) is described at anthesis. Sepals are described as persistent only if they are present on mature or near-mature capsules: in most cases they fall soon after anthesis. The operculum or 'window' occurs on the inner face of each mericarp and is a more or less distinct area of thin tissue that tears readily to release the enclosed seed.