PLANTS: Perennial herbs, lacking milky juice. STEMS: erect from a branched caudex. LEAVES: opposite, ovate to suborbicular. INFLORESCENCE: axillary. FLOWERS: calyx the lobes equal; corolla funnelform; stamens born near the base of the corolla tube, the anthers connivent and sagittate. FRUIT: a pair of follicles. SEEDS: comose at the apex. NOTES: 1 sp. in AZ, CA, UT. (Greek: kyklos = ring + aden = gland, referring to a perigynous, nectariferous disk). REFERENCES: McLaughlin, Steven, P. 1994. Apocynaceae. J. Ariz. – Nev. Acad. Sci. Volume 27, 164-168.