Cutaneous respiration
The skin of amphibians is a major site of respiration in all species for which measurements are available. Cutaneous respiration is the sole respiratory mode of lungless salamanders (family Plethodontidae) which lack lungs entirely yet constitute the largest family of salamanders. Cutaneous respiration in frogs and other amphibians may be the primary respiratory mode during colder temperatures.
Telmatobius culeus
While the lungs are greatly reduced, this frog has excessive amounts of skin, used to help the frog respire in the cold water in which it lives. The color is highly variable, but generally gray, brown or greenish above, and paler below.