Tree, to 40 m; branchlets glabrous. Leaves alternate, coriaceous; petioles 1-10 mm long, flattened toward apex, canaliculate and thickened at base; blades elliptic to obovate-elliptic, obtuse to bluntly acuminate at apex, the tip downturned and emarginate, cuneate at base, 6-16 cm long, 3-8.5 cm broad. Panicles terminal; branchlets dichotomously articulate, subcoriaceous, puberulent; bracts caducous; flowers (fide Cuatrecasas, 1961) many; pedicels thick, puberulent, 1-2.5 mm long; sepals orbicular, glabrous or nearly so, 6-7 mm long, bearing a single gland outside; petals oblong, obtuse at apex, ca 9 mm long and 3 mm wide, glabrous, greenish-white outside, white inside; stamens many (ca 80); filaments unequal, ca 8 mm long, linear, white, glabrous, united at base; anthers small, ovate-lanceolate, the connective thick at base, acute at apex; disk cupular, l mm high, minutely denticulate; ovary 3-4 mm high, hirsute; style 5 mm long. Drupes ovoid-ellipsoid, narrowed at both ends, ca 3.5 cm long and 1.2-1.7 cm thick; endocarp woody, 2.2-3.3 cm long, 1.2-1.7 cm thick, ellipsoid-ovoid, acute at apex, tapering to a rounded base, the surface moderately smooth, with 5 broad ribs, the ribs alternating with 5 oblong valves, the valves 1.8-2.1 cm long, 3-4 mm wide (only 1 of them removable); seed 1, oblong, ca 2 cm long. Garwood & Foster 400. Apparently rare; discovered recently between Wheeler Trail 2400 and 2500. Seasonality uncertain. Flowering has occurred in August. Mature-sized fruits have been collected in February, and the old endocarps may be seen on the ground year-round.