Scandent shrub, often to 30 m long; larger stems armed with stout spines (straight on juveniles, recurved on adults); smaller stems sometimes square; branchlets puberulent with minute trichomes, glabrous in age; tendrils forked, the arms coiled like watchsprings. Petioles ca 3 mm long, puberulent with minute trichomes; blades lanceolate to narrowly elliptic, very long-acuminate, obtuse to rounded at base, 2.5-14 cm long, l-4 cm wide, glabrous except for puberulent midrib below and tufted axils (with short white trichomes) of central pair of veins, entire, minutely and conspicuously undulate on margins, pliveined, the veins 3 (5), the secondary lateral veins +/- conspicuous in apical two-thirds of blade. Paniculate cymes terminal, usually hemispheric and bearing many flowers; calyx lobes (4) 5, lanceolate to narrowly ovate, acute to acuminate, l-2 mm long; corolla ca 2 cm long, (4) 5-lobed almost to base, the tube ca 0.6 mm long, the lobes oblong, obtuse, densely villous inside, ca twice as long as tube; anthers 5, ca 0.6 mm long, glabrous. Fruits globose, 6-7 cm diam, orange-yellow at maturity; exocarp ca 6 mm thick, smooth; seeds 5-11, obliquely pyramidal, 12-17 mm long, the mesocarp yellowish, tasty. Croat 14475.

Descripción: Plantas trepadoras o lianas con tronco gris o marrón y la corteza exterior exfoliante en láminas. Ramitas terminales de forma cuadrangular y con espinas y zarcillos. Hojas simples y opuestas, de 3-11 x 1.5-3.5 cm, ovadas o lanceoladas, con ápice acuminado, bordes enteros y base redondeada o aguda. Las hojas presentan tres nervaduras que salen a partir de la base. Pecíolo de 0.2-0.5 cm de largo. Inflorescencias en cimas o panículas terminales. Flores blancas. Frutos globosos, de 5-7 cm de largo, verdes, tornándose amarillos al madurar.

Especies Parecidas: Se puede confundir con LK strypa Strychnos panamensis LK2 , pero en S. panamensis las hojas son de mayor tamaño.