Habit: solitary, slender, decumbent to 3 m long then briefly erect to 1m tall. Stem: 5-7 mm diam., smooth, green, ringed, conspicuously and minutely white-spotted, internodes to 2-4 cm long. Leaves: 4-5, spreading, pinnate or less often bifid; sheath to 9 cm long, tubular, obliquely open apically, longitudinally striate-nerved; petiole to 9 cm long, ± rounded or slightly flattened and gray-green above, rounded and gray-green below; rachis to 12 cm long, angled and greenish above, rounded and greenish below with a faint yellow band extending onto sheath; petiole above and below and rachis above gray-green and densely white-spotted; pinnae 2-4 on each side of rachis, apical pair largest (or if bifid), to 19 x 3.5 cm with 5 conspicuous primary nerves, basal ones to 12 x 2.5 cm, lanceolate, falcate, acuminate, narrowed basally, stiff, ± thick and leathery, 2-3 prominent nerves, all pinnae with numerous secondaries, these ± faint, pinnae drying heavily striated. Inflorescences: infrafoliar, stiff and ascending, to 15-20 cm long. Staminate forked or with 3 rachillae, or infrequently spicate; peduncle to 5-6 cm long, 2.5-4 mm wide at base and there ± flattened, 1.5-3.5 mm diam. at apex and there rounded, ascending, greenish in flower; bracts 4, prophyll 5 mm long, 2nd bract 1 cm, 3rd 2-3 cm, 4th 4 cm, tubular basally, ± inflated apically, brownish at anthesis, leathery, acute-acuminate, bifid; rachis or flower-bearing portion ifspicate or rachillae to 10-12 cm long, to 2 mm diam., green, ascending. Pistillate spicate; peduncle similar to that of staminate but brownish or dull orange in fruit; bracts similar to those of staminate but greenish at anthesis; rachis or flower-bearing portion to 6 cm long, 2.5 cm diam., erect, greenish in flower, becoming thickened and dull orange in fruit. Flowers: Staminate in moderately dense spirals, maturing basally first and then attaining anthesis progressively toward the apex of axis, 2.5-3 x 2-2.5 mm, oblong to bullet-shaped, bright yellow, slightly sunken; calyx 1 x 2.5 mm, shallowly lobed, ringlike, pale green or yellowish, sepals connate and/or imbricate nearly to apex, broadly rounded apically; petals 2-2.5 x 2 mm, valvate, spreading, free nearly to base, acute, ± thick; stamens 1-1.5 mm high, filaments short, clear-colored, anthers 0.5 mm long, bilobed, brownish; pistillode 2-2.5 mm high, columnar, expanded basally and there 0.8 mm diam., whitish, apically 0.5 mm diam. and there yellow ageing to red. istillate in moderately dense spirals, 2.5-3 x 1.5-2 mm, bullet- shaped, yellow, slightly sunken; calyx 0.75 x 2.5-3 mm, shallowly lobed, ringlike, thickened, pale green, sepals connate in basal 2/3, rounded apically; petals 3 x 2.5-3 mm, imbricate nearly to apex, acute to mucronate apically; pistil 3 x 2 mm, ovoid, pale yellow-green, exceeding petals, stigma lobes sessile, short, recurved, clear-colored. Fruits: 6 mm diam., globose, black.
Windswept, moist, relatively open, dwarfcloud forest at or near the Continental Divide; 900-1,000 m elevation.