An eared seal, otariid, or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus (odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans, the southern Indian, and Atlantic Oceans. They are conspicuously absent in the north Atlantic.
Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semi-aquatic, and mostly marine mammals. They comprise the extant families Odobenidae, Otariidae, and Phocidae, with 34 extant species and more than 50 extinct species described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage. Pinnipeds belong to the clade Caniformia of the order Carnivora; their closest living relatives are musteloids, having diverged about 50 million years ago.
A bone bed is any geological stratum or deposit that contains bones of whatever kind. Inevitably, such deposits are sedimentary in nature. Not a formal term, it tends to be used more to describe especially dense collections such as Lagerstätte. It is also applied to brecciated and stalagmitic deposits on the floor of caves, which frequently contain osseous remains.
Enaliarctos is an extinct genus of pinnipedimorph, and may represent the ancestor to all pinnipeds. Prior to the discovery of Puijila, the five species in the genus Enaliarctos represented the oldest known pinnipedimorph fossils, having been recovered from late Oligocene and early Miocene strata of California and Oregon.
Desmatophoca is an extinct genus of early pinniped that lived during the Miocene, and is named from the Greek "phoca", meaning seal. A taxon of the family Desmatophocidae, it shares some morphological similarities with modern true seals. Two species are recognized: Desmatophoca oregonensis and Desmatophoca brachycephala. Little information exists regarding Desmatophoca, due to the small number of fossil samples obtained and identified.
Imagotaria is an extinct monotypic genus of walrus with the sole species Imagotaria downsi. Fossils of Imagotaria are known from the early late Miocene of California.
Wakaleo is an extinct genus of medium-sized thylacoleonids that lived in Australia in the Late Oligocene and Miocene Epochs. Although much smaller than its close relative, the marsupial lion, Wakaleo would have been a successful hunter. It had teeth specially designed for cutting and stabbing. The genus is from an extinct family of Vombatiformes, so it is distantly related to the herbivorous wombats.
Janjucetus is an extinct genus of cetacean, and a basal baleen whale (Mysticeti), from the Late Oligocene around 25 million years ago (mya) off south-east Australia, containing one species J. hunderi. Unlike modern mysticetes, it possessed large teeth for gripping and shredding prey, and lacked baleen, and so was likely to have been a predator that captured large single prey animals rather than filter feeding. However, its teeth may have interlocked, much like those of the modern-day filter-feeding crabeater seal, which would have allowed some filter-feeding behaviour. Its hunting behaviour was probably similar to the modern-day leopard seal, probably eating large fish. Like baleen whales, Janjucetus could not echolocate; however, it did have unusually large eyes, and so probably had an acute sense of vision. The only specimen was found on the Jan Juc beach, where the remains of the extinct whales Mammalodon, Prosqualodon and Waipatia have also been discovered.
Volia is an extinct monospecific genus of mekosuchine crocodylian closely related to Mekosuchus and Trilophosuchus. Volia is known from a collection of largely fragmentary remains including skull bones and limbs recovered from the Voli Voli and Wainibuku Caves on Viti Levu (Fiji), with similar remains having been found on Naigani. It was around 2–3 metres (7–10 ft) long, making it the largest predatory animal on the island and subsequently most likely the apex predator of the Pleistocene ecosystems of Fiji. It may have fed on giant iguanas, flightless birds or even fish. Like its closest relatives, it may have been more terrestrial than today's crocodiles.
Langstonia is an extinct genus of notosuchian crocodylomorph of the family Sebecidae. It lived in the middle Miocene, in the "Monkey Beds" of the Colombian Villavieja Formation. Langstonia was named in 2007 by Alfredo Paolillo and Omar Linares for fossils originally described by Langston in 1965 as Sebecus huilensis. Thus, the type species is L. huilensis.
Livyatan is an extinct genus of macroraptorial sperm whale containing one known species: L. melvillei. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous novel Moby-Dick about a white bull sperm whale. It is mainly known from the Pisco Formation of Peru during the Tortonian stage of the Miocene epoch, about 9.9–8.9 million years ago (mya); however, finds of isolated teeth from other locations such as Chile, Argentina, United States (California), South Africa and Australia imply that either it or a close relative survived into the Pliocene, around 5 mya, and may have had a global presence. It was a member of a group of macroraptorial sperm whales and was probably an apex predator, preying on whales, seals and so forth. Characteristically of raptorial sperm whales, Livyatan had functional, enamel-coated teeth on the upper and lower jaws, as well as several features suitable for hunting large prey.
Gustafsonia is an extinct genus of carnivoran belonging to the family Amphicyonidae. The type species, Gustafsonia cognita, was described in 1986 by Eric Paul Gustafson, who originally interpreted it as a miacid and named it Miacis cognitus. It was subsequently considered to be the only species of the diverse genus Miacis that belonged to the crown-group Carnivora, within the Caniformia, and it was ultimately assigned to the family Amphicyonidae. The type specimen or holotype was discovered in Reeve's bonebed, western Texas, in the Chambers Tuff Formation in 1986. The University of Texas holds this specimen. It is the only confirmed fossil of this species.
Scaldicetus is an extinct genus of highly predatory macroraptorial sperm whale. Although widely used for a number of extinct physeterids with primitive dental morphology consisting of enameled teeth, Scaldicetus as generally recognized appears to be a wastebasket taxon filled with more-or-less unrelated primitive sperm whales.
The Temblor Formation is a geologic formation in California. It preserves fossils dating back from the Late Oligocene to the Middle Miocene of the Neogene period. It is notable for the famous Sharktooth Hill deposit.
Gnatusuchus is an extinct genus of caiman represented by the type species Gnatusuchus pebasensis from the Middle Miocene Pebas Formation of Peru. Gnatusuchus lived about 13 million years ago (Ma) in a large wetland system called the Pebas mega-wetlands that covered over one million square kilometers of what is now the Amazon Basin.
Astorgosuchus is an extinct monospecific genus of crocodilian, closely related to true crocodiles, that lived in Pakistan during the late Oligocene period. This crocodile may have reached lengths of up to 8 m (26 ft) and is known to have preyed on many of the large mammals found in its environment. Bite marks of a large crocodile have been found on the bones of juvenile Paraceratherium, however if these were left by Astorgosuchus cannot be said with certainty. The genus contains a single species, Astorgosuchus bugtiensis, which was originally named as a species of Crocodylus in 1908 and was moved to its own genus in 2019.
Prototaria is an extinct genus of pinniped that lived approximately 15.97 to 13.65 mya during the Middle Miocene in what is now Japan. It belonged to the family Odobenidae, the only extant species of which is the walrus. Members of the genus Prototaria are believed to be the most basal imagotariine pinnipeds.
Osodobenus is an extinct genus of walrus from the Miocene to Pliocene of California. Osodobenus may have been the first tusked walrus and shows several adaptations that suggest it was a suction feeder, possibly even a benthic feeder like modern species. Three skulls are known showing pronounced sexual dimorphism, with the female lacking the same tusks as the male. Only a single species, Osodobenus eodon, is currently recognized.
Titanotaria is a genus of late, basal walrus from the Miocene of Orange County, California. Unlike much later odobenids, it lacked tusks. Titanotaria is known from an almost complete specimen which serves as the holotype for the only recognized species, Titanotaria orangensis, it is the best preserved fossil walrus currently known.
Atopotarus is an extinct genus of pinniped from the middle Miocene known from one specimen from Los Angeles County, California. It belongs to the extinct family Desmatophocidae, an early lineage of seal-like pinnipeds from the North Pacific.
