H.B.K., Nov. Gen. & Sp. 2:146, t. 113.1817
A. costaricensis (Klotzsch) Duch.
Slender, twining liana, conspicuously pilose on most parts. Leaves alternate; petioles slender, to 7 cm long; blades ovate, acute at apex, deeply cordate at base, 6-25 cm long, 5-15 cm wide, glabrescent above. Flowers solitary in axils, speckled white and brownish-purple; calyx expanded into a short ellipsoid balloon to 3 cm long, then constricted obliquely into a campanulate tube ca 2.5 cm long, finally opening into a narrow, fringed limb 1.5-2.5 cm long; corolla lacking; stamens 6, the anthers sessile and adnate to style; styles 6, connate; stigmas capitate. Capsules ovoid, ca 6 cm long and 4 cm wide, dehiscing from base, bearing many seeds; seeds disk-shaped, ca 1 cm diam. Croat 9011.
Occasional, around the Laboratory Clearing. Flowers mostly from January to May, sometimes later in the rainy season also. The fruits have not been seen on the island.
Central America and northern South America. In Panama, known from tropical moist forest in the Canal Zone, Bocas del Toro, Panama, and Darien.
See Fig. 217.