Spotted paddle-tail newt
"Pachytriton" species are stout-bodied, smooth-skinned aquatic newts. Their heads are large and flattened, and they have conspicuous labial folds and short, stubby legs and toes. They breathe through both lungs and skin. 
"P. brevipes" ranges from 5.5 to 7.5 in as an adult. It has prominent labial folds, long digits, and smooth skin, which differs from the tuberculate skin typical of newts.
Respiratory system of gastropods
Many of the very small freshwater limpets which live in cold water have lost the ability to breathe air, and instead flood their mantle cavity with water. Oxygen diffuses from the water to the snail's body directly.