Admetans

Admetans are the species native to Admetus. They appear as if they have been slowly evolving towards becoming aquatic, but because they prefer living on the surface, they have developed great affinity for underwater travel, but are unfortunately incredibly dependent on having access to both sea and land. 
The Admetans have enormous lung capacity, their bodies can adapt to pressure levels far greater than those a human can adapt to, they can hear and track by smell/taste under water and have webbing between their toes and fingers. Their skin is made to sustain prolonged exposure to the depths and they are cold-blooded, and do not do well in the sun - requiring constant submersion in water to survive if the temperature goes above a certain point. 
Their diet is almost entirely consistent of things oceanic, but they can survive on processed foods or other things, but have a natural high demand for fish oils and other things found in sea food. 
The admetans are bald, short and wiry in their build, quite strong and resilient but frail looking excepting their very large chest. They have very large feet and hands and have 10 phalanxes in their toes and fingers, giving them very long toes and fingers. Their skins are blue and greenish, leaning towards ocean colors, often with natural camouflage patterns.