PLANT: Decumbent and spreading perennial to 2 dm high. ROOTS large and fusiform. LEAVES: simple; petioles 3-18 cm long; blades nearly reniform or suborbicular to broadly ovate, 2-7 cm long, 2-8 cm wide, the margins entire to deeply lobed. INFLORESCENCE: short racemes with an initial axis length of 5-12 cm but lengthening in fruit to 1-2 dm. FLOWERS: 3-16 and fragrant; pedicels 2-8 cm long, slender, ascending in anthesis and with a linear basal bract; calyx bracts orbicular or broadly ovate to oblongfalcate, 5-10 mm long, 2-5 mm wide; calyx 1-1.5 cm long, the lobes cut one third to one half its length, viscid-pubescent without, glabrous within, the margins glandularciliate; corolla yellowish-brown externally, yellow to bronze-orange internally, the tube with pale blotches and maroon, reddish-brown or rust-colored spots in two rows internally and leading out to the throat and lobes, 2-3 cm long, slightly to strongly ventricose, infundibular to campanulate, the lobes spreading; filaments viscidpubescent at their base; pistil as long as or longer than the stamens. FRUIT: body very slender, 5-6 cm long and ca. 12 mm thick, crested dorsally and sometimes ventrally, the horns about twice as long as the body, the distal tooth on the dorsal suture often forming a slender horn. NOTES: In sandy soil and on dunes and gravelly hills: Cochise, Gila, Graham, Maricopa, Mohave, Pima, Pinal, Santa Cruz, Yavapai, Yuma cos.; below 1200 m (4000 feet); May-Sept; CA, NM, TX; n Mex., Peru. REFERENCES: Raul Gutierrez Jr., 2007, Vascular Plants of Arizona: Martyniaceae. CANOTIA 3 (2): 26-31.