Woody vines or sprawling shrubs; young stems narrowly 4-winged, older stems unwinged, warted by raised lenticels. Stipules minute, deciduous. Leaves simple, opposite, margins crenate to serrate. Flowers bisexual, in small cymes or solitary in axils; sepals 4, persisting and enlarging in fruit; petals 4 and minute, or apparently lacking; stamens 8; ovary semi-inferior, 4-locular; style bifid, with both lobes again shortly forked. Fruit a 1-seeded nut.
Endemic Australian genus, 1 species in south-west Western Australia, 1 in eastern Australia.