23. El Rincon Stream Frog
Image Source: Edge of Existence
These little guys live in one place — Patagonia, Argentina. The El Rincon stream frog is a very unique species. Due to the sub-zero temperatures on the Somuncura Plateau in Argentina, the frogs spend their lives in geothermal springs. The main reason for its gradual disappearance is two-fold. First, the creation of dams has cut into its habitat. Also, the introduction of rainbow trout to the springs has been detrimental to the frogs.