Radlk., Monogr. Serj. 345. 1875
Glabrous, tendriled liana; younger stems striate, the older stems grooved, flattened to 3-angled. Leaves trifoliolate and pinnate; petioles 2-7 cm long, with marginal ribs above; petiolules very short or to 13 mm long; leaflets lanceolate-elliptic, ovate or ± elliptic, acuminate, attenuate to rounded at base, entire to obtusely crenate above the middle, the teeth usually glandular, the terminal leaflet usually 10-14 cm long, 6-8 cm wide, the lateral leaflets somewhat smaller. Thyrses solitary in leaf axils or in terminal paniculate racemes, the ultimate branches densely bracteate and cincinnal; branches, pedicels, and calyces minutely tomentose; flowers white, ca 3 mm long; sepals 5, unequal, oblong to obovate, the 2 opposite the staminal cluster enlarged, obovate, petaloid; petals 4, obovate, glabrous but with villous margins, glandular inside near middle, to 1.7 mm long, all borne atop large glands, the anterior petals with an obscure, densely villous appendage medially and with a yellow crest, lobed to about midway and extending above the petals, the scales of the lateral petals lacking an obvious appendage; stamens 8; filaments villous to near the apex, the longest to 2.3 mm long, exserted; all anthers facing anterior petals; ovary minute, glabrous, 3-sided, glandular; styles 3, equaling ovary. Fruits ovate, subcordate, 4.5-5 cm long, less than 3.5 cm wide, glabrous, the cells ca 7 mm long, rugose, the veins of the wings prominulous. Croat 12668, Wetmore & Abbe 195, Woodworth & Vestal 638.
Rare; collected near Fuertes House and near the Redwood House at the end of Armour Trail and on Drayton Trail. Flowers and fruits in the dry season.
Distinguished by the glabrous, trifoliolate leaves with blunt, gland-tipped teeth.
At present known from Costa Rica to Colombia, but possibly more widespread in South America where a number of other similarly trifoliolate species occur. In Panama, known only from tropical moist forest on BCI and in Bocas del Toro.