Eschrichtiidae or the gray whales is a family of baleen whale with a single extant species, the gray whale, as well as four described fossil genera: Archaeschrichtius (Miocene), Glaucobalaena and Eschrichtioides (Pliocene) from Italy, and Gricetoides from the Pliocene of North Carolina. Some phylogenetic studies have found this family to be invalid, with its members nesting inside of the clade Balaenopteridae. The names of the extant genus and the family honours Danish zoologist Daniel Eschricht.
Rorquals are the largest group of baleen whales, comprising the family Balaenopteridae, which contains nine extant species in two genera. They include the largest known animal that has ever lived, the blue whale, which can reach 180 tonnes, and the fin whale, which reaches 120 tonnes ; even the smallest of the group, the northern minke whale, reaches 9 tonnes.
Baleen whales, also known as whalebone whales, are marine mammals of the parvorder Mysticeti in the infraorder Cetacea, which use keratinaceous baleen plates in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae, Balaenopteridae (rorquals), Eschrichtiidae and Cetotheriidae. There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychians, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago.
Balaenoptera is a genus of rorquals containing eight extant species. Balaenoptera comprises all but two of the extant species in its family ; the genus is currently polyphyletic, with the two aforementioned species being phylogenetically nested within it.
The sei whale is a baleen whale. It is one of ten rorqual species, and the third-largest member after the blue and fin whales. It can grow to 19.5 m (64 ft) in length and weigh as much as 28 t. Two subspecies are recognized: B. b. borealis and B. b. schlegelii. The whale's ventral surface has sporadic markings ranging from light grey to white, and its body is usually dark steel grey in colour. It is among the fastest of all cetaceans, and can reach speeds of up to 50 km/h (31 mph) over short distances.
The black geese of the genus Branta are waterfowl belonging to the true geese and swans subfamily Anserinae. They occur in the northern coastal regions of the Palearctic and all over North America, migrating to more southerly coasts in winter, and as resident birds in the Hawaiian Islands. Alone in the Southern Hemisphere, a self-sustaining feral population derived from introduced Canada geese is also found in New Zealand.
Otodus megalodon, commonly known as megalodon, is an extinct species of giant mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. O. megalodon was formerly thought to be a member of the family Lamnidae and a close relative of the great white shark, but has been reclassified into the extinct family Otodontidae, which diverged from the great white shark during the Early Cretaceous.
Eobalaenoptera is an extinct genus of baleen whale belonging to Balaenopteroidea.
Pachycrocuta is an extinct genus of prehistoric hyenas. The largest and most well-researched species is Pachycrocuta brevirostris, colloquially known as the giant short-faced hyena as it stood about 90–100 cm (35–39 in) at the shoulder and it is estimated to have averaged 110 kg (240 lb) in weight, approaching the size of a lioness, making it the largest known hyena. Pachycrocuta first appeared during the late Miocene. By 800,000 years ago, it became locally extinct in Europe, with it surviving in East Asia until at least 500,000 years ago, and possibly later elsewhere in Asia.
Megalibgwilia is a genus of echidna known only from Australian fossils that incorporates the oldest-known echidna species. The genus ranged from the Miocene until the late Pleistocene, becoming extinct about 50,000 years ago. Megalibgwilia species were more widespread in warmer and moist climates. Their extinction can be attributed to increasing aridification in Southern Australia.
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.
Plesiobalaenoptera is a genus of extinct rorqual which existed in Italy during the late Miocene epoch. The type species is P. quarantellii. It is the oldest known rorqual from the Mediterranean basin. Fossils have been found from sediments of the Stirone River in Northern Italy that were deposited during the Tortonian age, around 11 to 7 million years ago.
Orcinus citoniensis is an extinct species of orca identified in the Late Pliocene of Italy and the Early Pleistocene of England. It was smaller than the modern killer whale, 4 m (13 ft) versus 7 to 10 m, and had around 8 more teeth in its jaw. It may have resembled the modern killer whale in appearance, and could represent a transitional species between the modern killer whale and other dolphins. O. citoniensis could have hunted fish and squid in pods, and coexisted with other large predators of the time such as the orcinine Hemisyntrachelus and the extinct shark Otodus megalodon.
Pteranodontoidea is an extinct clade of ornithocheiroid pterosaurs from the Early to Late Cretaceous of Asia, Africa, Europe, North America and South America. It was named by Alexander Wilhelm Armin Kellner in 1996. In 2003, Kellner defined the clade as a node-based taxon consisting of the last common ancestor of Anhanguera, Pteranodon and all its descendants. The clade Ornithocheiroidea is sometimes considered to be the senior synonym of Pteranodontoidea, however it depends on its definition. Brian Andres in his analyses, converts Ornithocheiroidea using the definition of Kellner (2003) to avoid this synonymy.
Protororqualus is a genus of extinct rorqual from the late Pliocene of Mount Pulgnasco, Italy.
Plesiocetus is a genus of extinct rorquals found worldwide. It has had a chequered taxonomic history, having served as a wastebasket genus for a handful of mysticete species.
Eschrichtioides is an extinct genus of baleen whale known from the early Pliocene of Northern Italy. Its type species, E. gastaldii, had a complex taxonomic history, starting as a cetothere, then as an extinct member of Balaenoptera, before being finally recognized as a relative of the gray whale.
Nanophoca is an extinct genus of earless seals from the middle Miocene of Belgium.
