Ameiurus is a genus of catfishes in the family Ictaluridae. It contains the three common types of bullhead catfish found in waters of the United States, the black bullhead (Ameiurus melas), the brown bullhead (Ameiurus nebulosus), and the yellow bullhead (Ameiurus natalis), as well as other species, such as the white catfish (Ameiurus catus or Ictalurus catus), which are not typically called "bullheads". The species known as bullheads can be distinguished from channel catfish and blue catfish by their squared tailfins, rather than forked.