Cycladenia humilis is the sole member of the monotypic genus Cycladenia. Known by the common name Sacramento waxydogbane, it is an uncommon plant native to the southwestern United States. Collections have mostly been from California, although the species has also been reported from Utah and Arizona, mostly on gypsum soils.Kew World Checklist of Selected Plant FamiliesBiota of North America Paogram 2013 county distribution mapMcLaughlin, S.P. 1993. Apocynaceae A.L. Juss, Dogbane Family. Journal of the Arizona-Nevada Academy of Science 27:164-168. It is found at some elevation in several mountain ranges in the region. One of the four varieties of this plant, called the Jones cycladenia, is considered a threatened taxon.USFWS. Rule to determine Cycladenia humilis var. jonesii (Jones Cycladenia) to be Thr. Species. Federal Register May 5, 1986. This is a fleshy perennial herb with dull green leaves and pinkish lavender flowers. The flowers begin as rolled tubes shaped like pea pods and then open into colorful funnel-shaped blooms.
Nomenclature Cycladenia humilis Benth., Pl. Hartw. 323. 1849.Bentham. G. Plantas Hartwegianas imprimis Mexicanas 323. 1849.
Three varieties are recognized in addition to the autonymic var. humilis: Cycladenia humilis var. jonesii (Eastw.) S.L. Welsh & N.D. Atwood, Great Basin Naturalist 35(4): 333. 1976.S.L. Welsh & N.D. Atwood, Great Basin Naturalist 35(4): 333. 1976. = Cycladenia jonesii Eastw., Leafl. W. Bot. 3(7): 159–160. 1942.Eastwood, A. 1942. Leaflets of Western Botany 3(7): 159–160. Cycladenia humilis var. tomentosa (A. Gray) A. Gray, Syn. Fl. N. Amer. 2(1): 400. 1886.A. Gray. 1886. Synoptical Flora of North America 2(1): 400. = Cycladenia tomentosa A. Gray, Bot. California 1: 474. 1876.A. Gray. 1876. Geological Survey of California, Botany 1: 474. Cycladenia humilis var. venusta (Eastw.) Woodson ex Munz, Man. S. Calif. Bot. 379. 1935.Munz. P.A. 1935. Manual of Southern California Botany 379. = Cycladenia venusta Eastw., Bull. Torrey Bot. Club 29(2): 77. 1902.Eastwood, A. 1902. Bulletin of the Torrey Botanical Club 29(2): 77.
References
External links USDA Plants Profile Jepson Manual Treatment Recovery Outline for the Jones Cycladenia (cycladenia humilis var. jonesii) Fish and Wildlife Service Photo gallery