Guinea pigs are tailless rodents with compact body, short body, large head and short neck. They have small petal shaped ears on both sides of the head and small triangular mouth. As a result of selection breeding, there are 20 different phenotypes of hair color, and there are 13 different phenotypes of hair texture and length.
Guinea pigs have very short incisors and prismatic molars, which are always growing. Both sexes are similar except that they have specific glands. Body hair is black, white, gray, brown, chocolate, etc., but also with a variety of stripes.