Flora of Barro Colorado Island

Strychnos toxifera

Schomb. ex Benth., J. Bot. (Hooker) 3:240.1841

Urari

Liana with long reddish trichomes on most parts; oldest stems glabrous; stems divaricately branched; tendrils coiled. Petioles to 6 mm long; blades ovate to elliptic, acuminate, rounded to subcordate at base, 6-20 cm long, 3-8 cm wide, pliveined, the veins 3 (5). Cymes terminal, densely reddish-pilose; pedicels less than 5 mm long; flowers 5-parted; sepals lanceolate-linear, to 7 mm long; corolla white or yellow, salverform, the tube to 1.5 cm long, the lobes ca 2 mm long, densely bearded inside; anthers barely exposed at apex of corolla, ca 1 cm long; filaments attached to corolla tube; ovary subglobose, ca 1 mm diam; style exserted ca 2 mm; stigma capitate. Fruits globose, 4-7 cm diam, gray-green turning      bluish­-green; seeds usually 10-15, ca 2.5 cm diam. Croat 6766, 7278.

Occasional, in the forest. Flowers in the early dry sea­son. The fruits mature in the rainy season.

This species is the source of toxiferin, one of the most potent curare alkaloids (Blohm, 1962).

Costa Rica to Ecuador and Amazonian Brazil. In Pan­ama, known from tropical moist forest in the Canal Zone, San Blas, and Darien.

See Fig. 448.