Phocaena Phocaena is commonly known as the Harbour Porpoise, the smallest cetacean species found in the UK. It is a marine mammal that belongs to the Phocoenidae family, which is a group of six species that includes porpoises. The Harbour Porpoise is also known by other common names, including the Common Porpoise, Gulf of Maine Porpoise and Black Porpoise. Their habitats range from the Arctic Circle to the Bay of Biscay, and they are a common sight in coastal waters around the UK. The synonym for Phocaena Phocaena is "porpoise", and this species is often referred to as such by researchers and marine life enthusiasts.