Plant: perennial herb, vegetative parts typically roughened with a fine pubescence; stems ascending to rather decumbent, unbranched, 10-80 cm tall; milky sap Leaves: irregularly alternate, the petioles 2-11 mm long, the blades lanceolate to less often linear-lanceolate, 5-19 cm long, 6-27 mm broad, acute or infrequently obtuse at the base, long attenuate to an acute apex INFLORESCENCE: UMBELS solitary and terminal, 4-7 cm broad, sessile or more often long-pedunculate with the peduncles to 20(-30) cm long Flowers: large; calyx lobes 3-6 mm long; corolla greenish, uncommonly purple-tipped, bowl-shaped, the lobes curved-ascending, 9-12 mm long; hoods sessile and attached along the entire height of the column, oblong-tubular, "J"- to "C"-shaped, spreading-descending at the base and gradually curving upward near the middle, the upper portion erect to incurved, ca. 5-8 mm long, 2-2.6 mm broad at the median bulge, about as high as the gynostegium, the horns radially flat, attached in the top of the hoods, triangular, entirely included within the hood margins; anther wings 1.8-2 mm long; corpusculum 0.3-0.4 mm long, the pollinia 1.2-1.4 mm long Fruit: follicles erect on deflexed pedicels, 5-10 cm long REFERENCES: Sundell, Eric. 1994. Asclepiadaceae. J. Ariz. - Nev. Acad. Sci. Volume 27, 169-187.