Three new species of toads have been discovered living in Nevada's Great Basin in an expansive survey of the 190,000 square mile ancient lake bottom. Discoveries of new amphibians are extremely rare in the United States with only three new frog species discovered since 1985 – and toad species are even more rare, with the last species discovered north of Mexico, the now extinct Wyoming toad, in 1968."We've found the toads in small, wet habitats surrounded by high-desert completely cut off from other populations," Dick Tracy, a renowned biology professor at the University of Nevada, Reno, and lead scientist on the project, said. "These are absolutely new, true species that have been separated from other populations for 650,000 years."