Named after one of our users: Holbenilord.
Holstelids are aquatic mammals which live in the tropical oceans of Thanatos.
Holstelids resemble giant pine martens with flippers instead of legs. At 20 feet long, they are midgets compared to most animals on Thanatos. These mammals are dark blue to tan in color to blend in with the surrounding water, in order to hide from predators such as the tusked leviathan. Their teeth are thick, small and conical.
Holstelids are very specialized predators, feeding almost entirely on small to medium sized fish. In fact, these make up to 99% of the animal's diet. The rest consists of carrion.
Holstelids inhabit the tropical areas of the Thanatonian ocean, and prefer to swim close to shore. This is to avoid most of their predators. However, a few swim out into the open ocean, only to get killed by tusked leviathans.