Enhydra

Enhydra is a monotypic genus in the weasel family Mustelidae, containing the single living species the sea otter, native to the coasts of the North Pacific Ocean historically ranging in an arc from northern Japan to the central Baja California Peninsula in Mexico. The sea otter is markedly different from other mustelids: it lacks functional anal scent glands and can live its entire life without leaving the water. The genus represents a comparatively recent marine adaptation, having entered the ocean only around two million years ago in the Pleistocene.