Rarest amphibian

The Red List of Threatened Species lists two toads as "Extinct in the Wild": The Wyoming toad (Bufo baxteri) exists only within the Mortenson Lake National Wildlife Refuge in Wyoming, USA; believed extinct in 1980, it was rediscovered in 1987 but no known mating in the wild has occurred since 1991. The hundreds of remaining Kihansi spray toads (Nectophrynoides asperginis), a dwarf toad native to Tanzania, live at the Bronx Zoo, New York City, USA.