Large trees to 45 m tall; young branches glabrous. Leaves trifoliolate; petioles 4-20 cm long, terete to flattened, glabrous; leaflets petiolulate, the terminal petiolule 7-25 mm long, the lateral petiolules about equal to the! center one, the petiolules glabrous, terete or shallowly canaliculate; blades elliptic, apically acu- minate, the acumen 5-15 mm long, the margins entire to weakly crenate, basally rounded to subcuneate, glabrous on both surfaces, the terminal blade 12-34 cm long, 6-18 cm broad, the lateral blades equal or slightly smaller than the terminal one, the primary veins 8-18 pairs, plane above, prominent beneath, the venation prominulous beneath; stipels absent. Inflorescences clustered racemes; peduncles 6-10 cm long, glabrous, sparsely lenticellate towards the base; rachis 1-4.5 cm long, glabrous; flowering pedicels 4-6 cm long, 5-8 cm thick, glabrous, ebracte- olate. Flowers with the calyx campanulate, ca. 2 cm long, glabrous on the ex- terior, the lobes 5, rounded; corolla ca. 6-7 cm long, elliptic, glabrous, deep red on the exterior, paler within; stamens extremely numerous, over 700, the filaments caducous as a unit, basally united to 2 mm and then dividing into fused groups before becoming free above, the outer ones 7-8.5 cm long including the base, yel- low, the distal portion tuberculate, many shorter inner filaments present from 3.5 cm long and of all intermediate sizes, the inner filaments only apically tuber- culate, the anthers small; ovary globose, 4-locular, glabrous on the exterior, the styles 4, filamentous, 8-9 cm long, glabrous. Fruits subglobose to sublobate, to 15 cm long, the exocarp glabrous, lenticellate, the pericarp very thick and fleshy, detaching from the mesocarp and endocarp, the mesocarp and endocarp envelop- ing the seed to form a large stone ca. 7 cm broad, 5 cm long, the mesocarp be- coming lignified and hard, the exterior undulate with short rounded tubercles, the endocarp with a tuberculate exterior and a hard thin woody interior ca. 1 mm thick; only 1-2 subreniform seeds developing.