Densely leafy, almost hairless shrub, often with stiffly erect branches, up to 2m. Leaves leathery, oblong to oval, ascending, curved back at tips; solitary, radiate flowerheads on short, roughly hairy flower stalks, yellow rays and discs; fruits are ribbed and pitted, 5-7mm long.

Greek: osteon, bone; sperma, seed: referring to the hard seeds; hence common name for this genus 'Boneseed'.