Vaquita

The vaquita ( ; Phocoena sinus) is a species of porpoise endemic to the northern end of the Gulf of California in Baja California, Mexico. Reaching a maximum body length of (females) or (males), it is the smallest of all living cetaceans. The species is currently on the brink of extinction, and is listed as Critically Endangered by the IUCN Red List; the steep decline in abundance is primarily due to bycatch in gillnets from the illegal totoaba fishery.

== Taxonomy == The vaquita was defined as a species by two zoologists, Kenneth S. Norris and William N. McFarland, in 1958 after studying the morphology of skull specimens found on the beach. It was not until nearly thirty years later, in 1985, that fresh specimens allowed scientists to describe their external appearance fully.