南アメリカ大陸沿岸に広く分布するオットセイの仲間で、オスは150㎏、メスは50㎏ほどに成長します。ひれ状の前脚を使って素早く泳ぐだけでなく、陸上でも四肢を使って素早く動くことができ、崖なども登ることができます。アシカ類とよく似ていますが、頭が丸くて吻が短くとがっているほか、耳が大きく、アシカ類と比べて長く良質の毛を持っています。
South American fur seals widely distributed along the coast of the South American continent, and males grow to about 150kg and females to about 50kg. In addition to swimming quickly with fin-like fore legs, they can move quickly on land using limbs as well as climb cliffs. They are similar to sea lions, but they have round heads and short-pointed proboscis, large ears, and long dense fur compared to sea lions.