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.
Italian crested newt
"T. carnifex" is a member of a large family who all share common traits, one of which is the ability of this organism’s spleen to store large volumes of erythrocyte when the oxygen available goes beyond what is needed. Conversely, when the oxygen supply dips below necessary, the spleen of "T. carnifex" will release the red blood cells into the blood stream (as in cases of hypoxia, see below). This process will affect many aspects of the system, including the composition and volume of the blood. The surroundings of the animal will affect it. These surroundings include both the environment, and the physiological conditions the newt finds itself in. One such instance of this regulation is known as compensatory respiration, found during hypoxia. Hypoxia happens when there is an extremely low or limited amount of oxygen available to an organism.