| Orycterocetus Temporal range: Miocene | |
|---|---|
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Infraorder: | Cetacea |
| Family: | Physeteridae |
| Genus: | † Orycterocetus Leidy, 1853 |
| Species | |
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Orycteocetus is an extinct genus of sperm whale from the Miocene of the northern Atlantic Ocean.
Orycterocetus is a member of Physeteroidea closely related to crown-group sperm whales. The type species, O. quadratidens, was first named by Joseph Leidy on the basis of two teeth, two partial mandibular rami, and a rib from Neogene deposits of Virginia. [1] Two more species were subsequently described, O. cornutidens Leidy 1856 [2] and O. crocodilinus Cope, 1868, [3] the latter from the middle Miocene Calvert Formation.
Joseph Mellick Leidy was an American paleontologist, parasitologist and anatomist.
Basilosauridae is a family of extinct cetaceans. They lived during the middle to the early late Eocene and are known from all continents, including Antarctica. They were probably the first fully aquatic cetaceans. The group is noted to be a paraphyletic assemblage of stem group whales from which the monophyletic Neoceti are derived.
Belodon is a genus of phytosaur, a crocodile-like reptile that lived during the Triassic. Its fossils have been found in Europe and elsewhere. The type species, Belodon plieningeri, was named by prolific German paleontologist Christian Erich Hermann von Meyer in 1844.
Thespesius is a dubious genus of hadrosaurid dinosaur from the late Maastrichtian-age Upper Cretaceous Lance Formation of South Dakota.
Kentriodon is an extinct genus of toothed whale related to modern-day dolphins. Fossils have been found in North America, Europe and Japan. Several species have been described.
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.
Brygmophyseter, known as the biting sperm whale, is an extinct genus of toothed whale in the sperm whale family with one species, B. shigensis. When it was first described in 1994, the species was placed in the genus Scaldicetus based on tooth morphology, but this was later revised in 1995. In 2006, it was classified into the genus Naganocetus, which is considered to be a junior synonym. The only known specimen, a nearly complete skeleton, was dated to be around 16–15 million years old. Brygmophyseter is thought to have been 6.5–7 meters (21–23 ft) long, and it probably had 11 or 12 teeth in the upper and lower jaws. Brygmophyseter is part of a group of macroraptorial sperm whales which tended to be apex predators using their large teeth to catch struggling prey such as whales. It had a spermaceti organ which was probably used for biosonar like in the modern sperm whale. The whale has made an appearance on The History Channel's TV series Jurassic Fight Club.
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. Herman Melville often referred to whales as "Leviathans" in his book. 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.
Acrophyseter is a genus of extinct sperm whale that lived in the Late Miocene off the coast of what is now Peru. The genus comprises two species: A. deinodon and A. robustus. It is part of a group of macroraptorial sperm whales that all share several features for hunting large prey, such as deeply rooted and thick teeth. Acrophyseter measured 4–4.5 metres (13–15 ft) in length, making it the smallest macroraptorial sperm whale currently known. Because of its short pointed snout and strongly curved front teeth, it probably fed on the large marine vertebrates of its time, such as seals and other whales.
Thecachampsa is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from the eastern United States in deposits of Miocene age. Those named in the 19th century were distinguished primarily by the shape of their teeth, and have since been combined with T. antiquus. More recently erected species were reassigned from other genera, although their assignment to Thecachampsa has since been questioned.
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, including the Temblor and Itahashi formations. Based on previous estimates of juvenile specimens, Tsai (2017) suggested a body size of 12-15 m for P. yamaokai, akin to that of the gray whale.
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.
Peripolocetus is a genus of balaenid baleen whale from the middle Miocene of Kern County, California.
Pontobasileus is an archaeocete whale known from a fragment of a single tooth described by Leidy 1873. It can questionably be dated to the Eocene of Alabama.
Lophocetus is an extinct genus of dolphin belonging to the clade Delphinida that is known from late Miocene (Tortonian) marine deposits in California and Maryland. Although usually placed in Kentriodontidae, recent studies have found it only distantly related to Kentriodon.
Agorophius is an extinct genus of toothed whale that lived during the Oligocene period, approximately 32 million years ago, in the waters off what is now South Carolina.
Hoplocetus is an extinct genus of raptorial cetacean of the sperm whale superfamily, Physeteroidea. Its remains have been found in the Miocene of Belgium, France, Germany and Malta, the Pliocene of Belgium and France, and the Pleistocene of the United Kingdom and South Carolina.
Ischyrotherium is an extinct genus named by Joseph Leidy in 1856 for fossils from the lignite deposits in Nebraska. Originally considered an herbivorous cetacean, Leidy then reassigned it to Sirenia as a relative of manatees, before Edward Drinker Cope reclassified it as a non-mammalian, suggesting the new name Ischyrosaurus to better identify its reptilian origins, as he considered it a sauropterygian. Ischyrotherium was found alongside material from the hadrosaur Thespesius and turtles Compsemys and Emys, and the fish Mylognathus. The name Ischyrosaurus was also used by John Whitaker Hulke for the sauropod now known as Ornithopsis manseli, as he was unaware it was preoccupied by Cope.
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