Turcz., Bull. Soc. Imp. Naturalistes Moscou 32:267.1859
Tendriled liana, densely rufous-pubescent except sparsely so on upper surface of leaflets; stems 5-ribbed. Leaves biternate; petioles mostly 3-6.5 cm long, ribbed above; rachis margined, unwinged; leaflets ± elliptic, blunt to acuminate, abruptly tapered to base (especially lateral leaflets), remotely serrate-dentate, the terminal leaflet mostly 7-13 cm long, 3.5-5.5 cm wide, the lateral leaflets gradually smaller. Thyrses paniculate, terminal or upper axillary, the branches to 15 cm long; pedicels to 1 cm long; flowers white, ca 7 mm long, unisexual; sepals 5, tomentulose; petals 4, oblong-obovate, ciliolate, the 2 anterior petals subtended by a rounded gland, minutely pubescent on lower margins, depressed on outer face, white in staminate flowers, purple at apex in bisexual flowers, the scales of the anterior petals to two-thirds the length of the petals, the crest yellow, thin, emarginate, the appendage villous, slender, pendent to just above glands (scales of lateral petals lacking appendages); staminate flowers with the 5 longer stamens to 6.5 mm long, the shorter ones to 4 mm long; filaments sparsely villous; style nonfunctional; pistillate flowers with the stamens 8, nonfunctional, to 3.5 mm long; ovary pubescent; style 3-4 mm long; stigmas 3, ca 1 mm long. Fruits subrectangular-oblong, ca 4 cm long, the cells rufous-pubescent, subapical, hirtellous and setose with a hornlike projection, the wings hirtellous. Croat 7823, 12714, 12715.
Occasional. Flowers in the earliest part of the dry season, with the fruits maturing in the middle to late dry season.
This species is possibly dioecious and is unusual for its large flowers.
Honduras to Panama. In Panama, known from tropical moist forest in the Canal Zone, Colón, and Darien.
See Fig. 347.