Plant: herbacious vine; Stems pilose at base, glabrous upwards or sparsely pubescent at the nodes; milky sap Leaves: linear, 1-6 cm long, ca. 0.2 cm broad, more or less revolute, glabrous above, sparsely pubescent to glabrate below, the margins sparsely ciliate; petioles absent or indistinct INFLORESCENCE: umbelliform, ca. 1 cm across, the peduncles mostly 1-2 cm long Flowers: ca. 3-4 mm long; calyx lobes 1-2 mm long; corolla yellowish, cylindric-campanulate, the tube 2-3 mm long, pubescent inside, the lobes incurved and hooded, their tips more or less closing the corolla tube; crown absent; anther wings 0.5-0.6 mm long; corpusculum 0.3-0.4 mm long, the pollinia oblong-obovate, ca. 0.4 mm long; stigma head apically rounded Fruit: FOLLICLES ca. 6-7 cm long Misc: deserts, sand dunes; 150-900 m (500-3000 ft); Apr-Jun REFERENCES: Sundell, Eric. 1994. Asclepiadaceae. J. Ariz. - Nev. Acad. Sci. Volume 27, 169-187.