"Ring species of the salamander Ensatina in the western United States. One species (E. oregonensis) is found in the north and up into Oregon and Washington. It then divides in northern California and forms a more or less continuouis ring around the San Joaquin Valley. The Salamanders vary in form from place to place, and consequently they have been given a number of taxonomic names. Where the coastal and inland sides of the ring meet in southern California, the salamanders behave as good species at some sites (black zones on the map)." [Picture from Thelander (1994); text from Hickman et al. (1993)]