Radlk., Sitzungsber. Math.-Phys. Cl. Königl. Bayer. Akad. Wiss. München 20:230.1890
A. panamensis Radlk.
Slender, polygamous tree, usually 5-10(20) m tall; stems terete, glabrous except when young. Leaves trifoliolate; petioles somewhat flattened laterally, 2-5 (7) cm long, strigose; leaflets ± elliptic, subsessile, acuminate at apex, acute and sometimes inequilateral at base, 2.5-26 cm long, 1.5-7.5 cm wide, remotely serrate, ± glabrous but with sparsely pubescent veins and sometimes tufts of trichomes in axils of veins below. Thyrses puberulent, simple or paniculate, chiefly axillary; flowers 4-parted, campanulate, cream or greenish-white, ca 2 mm wide, pedicellate; sepals ciliolate, orbicular to obovate; petals obovate, l-2 mm long, the scales united with petals to near apex, densely villous, each subtended by a yellowish basal gland; staminate flowers with the stamens 8, well exserted, to ca 2.3 mm long, clustered on one side of the flower; filaments villous at least near base; pistillode obscure; pistillate flowers with the stamens less than 1 mm long, included; ovary 2-celled, minutely hispidulous; style borne between 2 cells of ovary, 1.5-2 mm long, persisting in fruit but very oblique, held at base of fruit; stigmas 2, recurved, densely papillate. Fruits of 2 obovoid cocci (1 often aborting), 6-9 mm long, yellow to orange, finally red and glabrate at maturity with a thin fleshy pericarp covering the seed; seed 2-3 mm diam. Croat 5862,10754.
Frequent in the forest, especially the young forest; possibly most abundant along the shore. Flowers in the dry season (January to May), with the fruits maturing in the early rainy season (May to August).
The species is variable throughout Panama. BCI plants are generally glabrate on the surface of the leaves and sparsely pubescent on the veins, sometimes with axillary tufts of trichomes in the vein axils. The closely related A. occidentalis Sw. (not on BCI) is puberulent to villous over the entire leaf surface.
Mexico to Panama; West Indies. In Panama, known principally from tropical moist forest in the Canal Zone, Chiriqui, Veraguas, Los Santos, Panama, and Darien; known also from tropical dry forest in Los Santos and Coclé, from premontane moist forest in Los Santos (Punta Mala), from premontane wet forest in Chiriqui (Tolé), and from tropical wet forest in Coclé, (El Valle). Standley (1928) reported the species to be occasional on the Atlantic slope of the Canal Zone. Reported from premontane rain forest in Costa Rica (Holdridge et al., 1971).