shoulders and abandoned agricultural fields. The population in the Carrizo Plain National Monument was discovered in 2002 and is being managed by the Bureau of Land Management. Conservation status It once was believed that Erodium was a serious threat to the sphinx moth because of larval mortality after eggs were mistakenly deposited on this plant. However, emerging research shows that female moths deposit eggs on plants indiscriminately, and the larvae wander to find a suitable host. Erodium is never fed upon. Until 1974 the species was considered to be extinct, at which time a surviving population was found in the eponymous Kern County. Sphinx moths are valuable to insect collectors, who may pose a threat to these small populations. Pesticide or herbicide application could also endanger the moth. But the greatest threat is likely habitat loss and alteration. This species is extremely rare and in most years field surveys of the Walker Basin population have found few or no individuals. However, desert Lepidoptera often show great natural variations in population size in response to climatic conditions, and surveys may more accurately reflect population status in years with above-normal rainfall. Notes References P.M. Jump, T. Longcore, and C. Rich. 2006. Ecology and Distribution of a Newly Discovered Population of the Federally Threatened Euproserpinus euterpe. Journal of the Lepidopterists' Society 60(1): 41-50. C. Thelander, Life On the Edge: A Guide to California's Endangered Natural Resources. Edition 1994. BioSystem Books. Santa Cruz, California. p 442-443. P.M. Tuskes and J.F. Emmel. 1981. The life history and behavior of Euproserpinus euterpe (Sphingidae). Journal of the Lepidopterists' Society 35:27-33. U.C. Berkeley, Essig Museum of Entomology. California's Endangered Insects U.S. Fish and Wildlife Service. Kern Primrose Sphinx Moth Recovery Plan. 1984. Portland, Oregon. External links Xerces Society Species Profile Life History and pictures of adults and larval instars Euproserpinus Endemic fauna of California Moths of North America Fauna of the Sierra Nevada (United States) Moths described in 1888 ESA threatened species