Shrubs or subshrubs; branches usually ridged or longitudinally striate, terete or sometimes flattened, occasionally spine-tipped. Leaves alternate, simple, unifoliolate or rarely (not in Victoria) 3–5-foliolate, sometimes reduced to minute scales; stipules usually small and inconspicuous. Flowers 1–several per axil, usually subtended by a few small scales as well as the bract; bracteoles 2, attached near or above midway of pedicel; upper lobes of calyx either largely united or much broader than the others; staminal sheath split open on upper side; anthers alternately basifixed and dorsifixed, the latter usually shorter. Pods (1 or)2–several-seeded, the valves separating along both sutures; seeds elliptic to ovate, compressed, with a small hilum surrounded by a collar-like aril.
Endemic genus of 12 species, occurring in all mainland States.