An unexpected hairy settler

In fact, besides bats, seals and cetaceans, Antarctica has recently welcomed a new species of mammal from the mustelid family: the antarctic newotter (Marinolutra terrestris). The ancestor of this large otter was once found in all of the kelp forests that fragmentarily connect Tierra del Fuego to the Antarctic peninsula. Thanks to periodical stepping-stone corridors, small populations have successfully colonized the colder but richer marine ecosystem of Antarctica. Now, the newotter can be found across all the antarctic coast, with at least one population that has moved into freshwater ecosystems (Marinolutra terrestris ssp. polarica). 
Newotters possess strong and short jaws, perfect to break the hard shell of snails and crustaceans of the kelp forest. Riparian newotters have a less durophagous diet, going also after fish, aquatic birds and sometimes terrestrial prey (ground rails, bird eggs, carrion, etc.).

Despite deriving from aquatic ancestors, newotters have never developed fins: improving their swimming ability wasn't probably necessary due to their diet, which never included fast prey (a sort of parallel evolution with the holocenic sea otter from the boreal hemisphere). Also, unlike other marine species, the newotter must return to the coast to reproduce. It's impossible to state if their ancestral parent was the marine species Lontra felina or another clade of marine otters that evolved in the last 20 million years. While their past remains a mystery, their future seems bright in Antarctica.