Procyon is a genus of nocturnal mammals comprising three species commonly known as raccoons in the family Procyonidae. The most familiar species, the common raccoon (P. lotor), is often known simply as "the" raccoon, as the two other raccoon species in the genus are native only to the tropics and less well known. Genetic studies have shown that the closest relatives of raccoons are the ring-tailed cats and cacomistles of genus Bassariscus, from which they diverged about 10 million years ago.