There are no known subspecies of Vaquita. This is because they have such a limited distribution in one singular location, with no evolutionary separation. At one point, however, the Vaquita and Burmeister’s Porpoise might have been the same species, millions of years ago.
Although geographically closer to the Harbor Porpoise off the coast of central California around 1,500 miles away, the Vaquita is more closely related to a Southern Hemisphere species of porpoise, the Burmeister’s Porpoise. The Burmeister’s Porpoise occurs some 3,000 miles away in Peru, and further south. Most likely, the Vaquita evolved from an ancestral population that moved northward into the Gulf of California around one million years ago during the Pleistocene era.