Tree, to 40 m tall, to 75 cm or more dbh; buttresses 1-2 m high; outer bark reddish-brown, hard, moderately coarse, with weak vertical fissures; inner bark pale; wood reddish-brown, hard; stems minutely ferruginous-hirtellous, at least when young, angulate on drying. Petioles 5-15 mm long, glabrate; blades oblong to oblong-elliptic, acute to short- acuminate, obtuse to rounded at base, 5.5-18 cm long, 2-8 (10) cm wide, hirtellous to glabrate on midrib and veins, the margins irregular. Panicles terminal, bearing few to many flowers; flowers with a faint, somewhat unpleasant aroma, precocious or occurring with new leaves, sometimes on a few leafless branches while other branches fully leaved; pedicels 1.5-2.5 cm long; calyx deeply 6-lobed, the lobes imbricate, +/- ovate, obtuse; petals 6, lavender to rose, to ca 2.5 cm long, rounded at apex, often minutely fimbriate, of unequal widths, 2 petals +/- spatulate, usually broader, to 1.3 cm wide, the others narrowly oblong, to 8 mm wide; androphore produced into a prominent hood spirally involute then reversely revolute, the whole structure subglobular, slightly broader than high, to 1.7 cm wide, +/- magenta and white, the basal part of the androphore shaped like a soap dish, whitish inside, magenta on margins; stamens mostly 13-18, arranged around the stigmatic orifice, ca 1 mm long; anthers rounded, flattened, about as long as filament; ovary 3-celled; stylar orifice ca 1.5 mm diam; stigma +/- sessile, minutely 3-radiate. Capsules woody, narrowly cylindrical-campanulate pyxidia, slightly asymmetrical, brown, conspicuously lenticellate, 7-12 cm long, 3-4 cm diam, pendent at maturity; cap and the strong central placenta falling free to allow dispersal of seed through orifice; seeds several per locule, prominently winged, thin, ca 7 cm long. Croat 8061, 16507. Rare; only a few individuals known on the island. Flowers from July through August, but an individual may flower only once every two years. Allen (1956) reported flowering in late September on the Osa Peninsula in Costa Rica. The fruits mature in February and March.