Cetotheriidae

species of mammal

Cetotheriidae is a family of baleen whales (parvorder Mysticeti). The family is known to have existed from the Late Oligocene to the Early Pleistocene before going extinct. Although some phylogenetic studies conducted by recovered the living pygmy right whale as a member of Cetotheriidae, making the pygmy right whale the only living cetotheriid, other authors either dispute this placement or recover Neobalaenidae as a sister group to Cetotheriidae.

Cetotherium ("whale beast") is an extinct genus of baleen whales from the family Cetotheriidae.

Herpetocetus is a genus of cetotheriid mysticete in the subfamily Herpetocetinae. Considerably smaller than modern baleen whales, Herpetocetus measured only 3 to 4 meters in length. Additionally, due to the structure of its jaw, it was unable to open its mouth as wide as modern baleen whales, making it incapable of lunge feeding.

Piscobalaena is an extinct genus of cetaceans, which lived from the Middle to Late Miocene epochs (about 11.6 to 5.3 million years ago) in Peru and Florida. Its fossils have been found in the Pisco Formation of Peru and the Bone Valley Formation of Florida. At least some individuals of this diminutive whale were preyed on by the shark O. megalodon.

Brandtocetus is a genus of cetotheriid mysticete in the subfamily Cetotheriinae. The type and only species is Brandtocetus chongulek from the late Miocene (Tortonian) of the Kerch Peninsula in Crimea.