Riffle beetles (Coleoptera: Elmidae) of Death Valley National Monument, California

Three species of Elmidae occur in Death Valley National Monument: Stenelmis calida is in three springs in the Ash Meadows area; Microcylloepus formicvideus is only in Travertine Springs; and Microcylloepus similis is in several springs throughout Death Valley and Ash Meadows. Only permanent springs support elmids. Considerable morphological variation occurs in the disjunct populations of M. similis . The evolution of elmids in Death Valley National Monument is equivalent to that of the local pupfish ( Cyprinodon spp.).