Large terrestrial herb, ca 2 m tall; stems to 30 cm high and 12 cm thick. Leaves to 1.8 m long, closely spiraled, clustered at apex; petioles about half the length of blade; blades broadly obovate, to ca 1 m long and 60 cm wide near apex, bifid, tapering to narrow base, decurrent onto petiole and continuous with broadly vaginate wing of petiole, becoming very much dissected in age, the surfaces pleated, the ribs 3, the lateral ribs branching from the midrib near base, the segment ribs prominently raised on upper surface, with furfuraceous scales scattered on lower surface; juvenile leaves similar to adults in shape, at first entire, splitting in maturity. Inflorescences from leaf axils, often several; peduncles to ca 20 cm long; spathes usually 3 or 4, +/- oblong, 6-10 cm long, widely spaced below spadix, the outer one keeled; spadix cylindrical, blunt at apex, 4.5-6 cm long, white in flower, becoming green in fruit; staminate flowers alternating with short, conical pistillate flowers, densely covering spadix, but soon falling free; perianth lobed; pistillate flowers with tepals thick, longer than style at anthesis, light green; staminodia to ca 6 cm long, caducous; stigmas medial, narrow, elongated, dark green. Seeds ca 1.5 mm long and ca 1 mm wide. Croat 10204, 14088. Uncommon, on creek banks and in ravines in the vicinity of the Laboratory Clearing. Flowers from late dry season to the middle of the rainy season, March to August. Mature fruits have been seen from June to September. Known only from Panama in tropical moist forest in the Canal Zone, San Blas, and Chiriqui and from tropical wet forest in Colón.