Eschrichtiidae or the gray whales is a family of baleen whale with a single extant species, the gray whale, as well as three described fossil genera: Archaeschrichtius and Eschrichtioides from the Miocene and Pliocene of Italy respectively, and Gricetoides from the Pliocene of North Carolina. More recent phylogenetic studies have found this family to be invalid, with its members nesting inside the Balaenopteridae. The names of the extant genus and the family honours Danish zoologist Daniel Eschricht.
Neobalaenidae is a family of baleen whales including the extant pygmy right whale. Although traditionally considered related to balaenids, a recent phylogenetic study by Fordyce and Marx (2013) recovered the living pygmy right whale as a member of Cetotheriidae, making it the only extant cetotheriid, but not all authors agree with this argument.
Cetotherium is an extinct genus of baleen whales from the family Cetotheriidae.
Ontocetus is an extinct genus of walrus, an aquatic carnivoran of the family Odobenidae, endemic to coastal regions of the southern North Sea and the southeastern coastal regions of the U.S. during the Miocene-Pleistocene. It lived from 13.6 mya—300,000 years ago, existing for approximately 13.3 million years.
Cetotheriidae is a family of baleen whales. The family is known to have existed from the Late Oligocene to the Early Pleistocene before going extinct. Although some phylogenetic studies conducted by Fordyce & Marx 2013 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.
Parietobalaena is an extinct genus of baleen whale, belonging to the family Pelocetidae. Fossils are found in Miocene-aged marine strata in North America, Europe, Australia and Japan.
Mesocetus is an extinct genus of baleen whale from the Miocene of Europe.
Diaphorocetus is an extinct genus of odontocete cetacean belonging to Physeteroidea. Its remains were found in the Monte León Formation of Argentina, dating to the Early Miocene.
Balaenula is an extinct genus of cetacean.
Heterocetus is a dubious genus of extinct cetacean.
Balaenotus is an extinct genus of cetaceans from the Pliocene of Belgium.
Herpetocetus is a genus of cetotheriid mysticete in the subfamily Herpetocetinae.
Protororqualus is a genus of extinct rorqual from the late Pliocene of Mount Pulgnasco, Italy.
Plesiocetus is a genus of extinct balaenopterids found worldwide. It has had a chequered taxonomic history, having served as a wastebasket genus for a handful of mysticete species.
Cetotheriopsis is a genus of extinct cetaceans of the family Cetotheriopsidae.
Nannocetus is an extinct baleen whale belonging to the family Cetotheriidae.
Isocetus is an extinct genus of baleen whale belonging to the clade Thalassotherii. Remains have been found in middle Miocene marine deposits in Belgium.
Eudelphis is an extinct genus of sperm whale belonging to Physeteroidea that lived in the ancient North Sea basin about 16-11 million years ago, during the middle Miocene (Langhian).
Atlanticetus is a genus of extinct mysticete known from the Early Miocene of Italy and the US Eastern Seaboard. As of February 2021, the genus was not accepted by the Paleobiology Database.
