Dixie Valley toad facts for kids

The Dixie Valley toad (Anaxyrus williamsi or Bufo williamsi) is a species of toad in the family Bufonidae. It is endemic to Churchill County in the state of Nevada in the United States. It is the first new toad species to be described from the United States since the description of the now-extinct in the wild Wyoming toad (A. baxteri) about 49 years prior.

It was formerly considered an isolated population of the common western toad (A. boreas) until physical and genetic analyses found it to be a separate species. It can be physically distinguished from the western toad by the scattered gold-colored flecks that cover its olive body, and is also the smallest member of the A. boreas species complex in the region. It is descended from an ancestor that inhabited the large lakes and wetlands that covered the Great Basin in the Pleistocene until the receding water isolated the different populations, leading to speciation. The Dixie Valley toad is only found in a small complex of vegetated spring-fed marshlands in Dixie Valley, one of the hottest and geothermally active systems in the region. The surrounding areas are largely arid land with little aquatic resources, isolating A. williamsi from the rest of the world. While it is considered locally abundant within its extremely small range, it is threatened by plans to build a geothermal power plant, which can degrade the marshland that it lives in.