Tree, to 26 m tall; trunk buttressed and fluted, to 75 cm dbh; outer bark thin, light-colored; branchlets acutely tetragonal to terete or compressed, densely puberulent when young. Leaves trifoliolate, opposite; petioles 1.3-9.5 cm long, finely appressed-puberulent; petiolules 1-8 mm long, the central one longest, flattened, margined; leaflets unequal with the lateral pair smaller and narrower, the central leaflet rounded and acuminate at apex, acute to acuminate at base, 4-22 cm long, 2.5-10.5 cm wide, entire, shiny and glabrous above, finely puberulent on veins beneath when young, becoming glabrate in age. Inflorescences axillary, solitary, 3.5-14 cm long, 4-6 cm wide, dichotomously branched, finely puberulent throughout, bearing many flowers; peduncles conspicuously flattened, 4.5-7.5 cm long; pedicels 1-3 mm long; bracts ca 1.5 cm long and 4 mm wide; flowers not seen, reportedly blue and lavender. Fruits not seen.