United States, California, Lassen, Modoc Plateau; Big Valley, Ash Creek State Wildlife Area; 6.1 air-mile west of Adin, 5.6 air-miles northeast of Bieber, app. 0.5 mile north of Wayman Barn; Ash Creek floodplain, near bermed pond. T39N, R8E, se ¼ ne ¼ Sec. 33. Big Swamp 7.5' quad.