Macaques are a genus of catarrhine primates of the family Cercopithecidae. Apart from humans, they are the only primates that have widely transcended the boundaries of the tropics, reaching as far as North Africa, Gibraltar, Europe, China and Japan. Twenty-two species have been described, including the well-known rhesus macaque and the Gibraltar monkey. Some of these species, such as the Gibraltar monkey, lack tails, while others have more or less developed tails.