Spectacled Porpoises inhabit the the waters of certain offshore islands and the southern Atlantic coast of South America. In 1985 Barnes reclassified it into its own genus, Australophocaena , which refers to its southern distribution. Spectacled Porpoises are small, with a large rounded dorsal fin.
Females have a more triangular fin.
The upper body is glossy blue-black in colour, with a sharp line portraying the change to white on the lower sides and underneath. This white area may expand with age. There is a white stripe along the upper side of the tail stock. A black patch is present around each eye, surrounded by a fine white line. The lips are black and one or two dark grey stripes lead from the lips to the flippers, extending to trail down the leading edge.