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List Of Extinct Cetaceans
The list of extinct cetaceans features the extinct genera and species of the order Cetacea. The cetaceans (whales, dolphins and porpoises) are descendants of land-living mammals, the even-toed ungulates. The earliest cetaceans were still hoofed mammals. These early cetaceans became gradually better adapted for swimming than for walking on land, finally evolving into fully marine cetaceans. This list currently includes only fossil genera and species. However, the Atlantic population of gray whales (''Eschrichtius robustus'') became extinct in the 18th century, and the baiji (or Chinese river dolphin, ''Lipotes vexillifer'') was declared "functionally extinct" after an expedition in late 2006 failed to find any in the Yangtze River. Suborder Archaeoceti Family Ambulocetidae (Eocene) * ''Ambulocetus'' * ''Himalayacetus'' * '' Gandakasia'' Family Basilosauridae (Late Eocene) * Basilosaurinae ** ''Basilosaurus'' ** ''Basiloterus'' ** ''Eocetus'' ** ''Platyosphys'' * Dorudonti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorudon BW
''Dorudon'' ("spear-tooth") is a genus of extinct basilosaurid ancient whales that lived alongside ''Basilosaurus'' 40.4 to 33.9 million years ago in the Eocene. It was a small whale, with ''D. atrox'' measuring long and weighing . ''Dorudon'' lived in warm seas around the world and fed on small fish and mollusks. Fossils have been found along the former shorelines of the Tethys Sea in present-day Egypt and Pakistan, as well as in the United States, New Zealand, and Western Sahara. Taxonomic history described ''Dorudon serratus'' based on a fragmentary maxilla and a few teeth found in South Carolina. He concluded that the teeth must have belonged to a mammal since they were two-rooted, that they must have been teeth from a juvenile since they were hollow, and also noted their similarity to the teeth then described for ''Zeuglodon'' (''Basilosaurus''). When exploring the type locality, Gibbes discovered a lower jaw and twelve caudal vertebrae, which he felt obliged to assign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysocetus
''Chrysocetus'' (from Greek ''chrysous'', "golden", and ''ketos'', "whale", in reference to the gold-colored bones of the type specimen) is a genus of extinct early whale known from Late Eocene-aged fossils of the eastern United States and western Africa. Taxonomy The type species, ''Chrysocetus healyorum'', is based on a single subadult specimen from the late middle or early late Eocene of Orangeburg County, South Carolina (, paleocoordinates ). The holotype, SCSM 87.195, consists of a partial skull with lower jaws, ten teeth, and the hyoid apparatus; 21 vertebrae, some ribs and a sternum; a partial left forelimb; and partial innominates. A second species, ''Chrysocetus fouadassii'', is known from Bartonian-age deposits in the Western Sahara.Philip D. Gingerich and Samir Zouhri (2015). "New fauna of archaeocete whales (Mammalia, Cetacea) from the Bartonian middle Eocene of southern Morocco". Journal of African Earth Sciences 111: 273–286. doi:10.1016/j.jafrearsci.2015.08.00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancalecetus
''Ancalecetus'' (from Greek ''ankale'', "bent arm", and ''ketos'', "whale") is an extinct genus of early whale known from the Late Eocene (Priabonian, ) Birket Qarun Formation (, paleocoordinates ) in Wadi Al-Hitan, Egypt. The species is named after anthropologist and primate researcher Elwyn L. Simons who discovered the type specimen in 1985. The holotype is a partial cranium (the top of the skull was destroyed by erosion), both dentaries, 20 vertebrae and some sternal elements, partial ribs, and most of both forelimbs. ''Ancalecetus'' differs from other archaeocetes and modern whales in having narrow scapulae, very limited mobility in the shoulder joint, and fusion of the humerus, ulna, and radius at the elbow joint. In the wrist, the carpal bones are small like in ''Zygorhiza'', but, unlike in this other basilosaurid, the magnum is fused with the trapezoid in ''Ancalecetus''. Forelimbs The well-preserved forelimbs are the most distinctive parts of ''A. simonsi''. A broad s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorudontinae
Dorudontinae are a group of extinct cetaceans that are related to ''Basilosaurus''.. Retrieved July 2013. Classification * Subfamily Dorudontinae ** Genus ''Ancalecetus'' *** ''Ancalecetus simonsi'' ** Genus ''Chrysocetus'' *** ''Chrysocetus fouadassii'' *** ''Chrysocetus healyorum'' ** Genus ''Cynthiacetus'' *** ''Cynthiacetus maxwelli'' *** ''Cynthiacetus peruvianus'' ** Genus ''Dorudon'' *** ''Dorudon atrox'' *** ''Dorudon serratus'' ** Genus ''Masracetus'' *** ''Masracetus markgrafi'' ** Genus ''Saghacetus'' *** ''Saghacetus osiris'' ** Genus ''Stromerius'' *** ''Stromerius nidensis'' ** Genus ''Zygorhiza ''Zygorhiza'' ("Yoke-Root") is an extinct genus of basilosaurid early whale known from the Late Eocene (Priabonian, 38–34 Ma) of Louisiana, Alabama, and Mississippi, United States, and the Bartonian (43–37 Ma on the New Zealand geologic time ...'' *** ''Zygorhiza kochii'' Notes References * Basilosauridae {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platyosphys
''Platyosphys'' is a genus of basilosaurid from Middle Eocene (Bartonian) of the eastern United States and Ukraine. Taxonomy The type species, ''Platyosphys paulsoni'', was originally described as '' Zeuglodon paulsoni'' in 1873 on the basis of several vertebrae from a Bartonian-age horizon in southern Ukraine. In his 1936 monograph regarding Archaeoceti, Remington Kellogg recognized the distinct nature of the taxon and coined the new genus ''Platyosphys'' for ''Z. paulsoni''. Another new species of ''Platyosphys'', ''P. einori'', was coined for vertebrae, a scapula, and rib fragments in 2001. In the original description of ''Basilotritus ''Basilotritus'' is a genus of basilosaurid early whale known from the early late Middle Eocene (late Lutetian to Bartonian, ) Kiev Formation of the Ukraine, Stockletten Formation of Germany, Tongeren Formation of the Netherlands, Giushi F ...'', ''Platyosphys'' and its constituent species were considered ''nomina dubia'' because th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocetus
''Eocetus'' is an extinct protocetid early whale known from the early late Eocene (Bartonian, ) Giushi Formation in Gebel Mokattam, (, paleocoordinates ) outside Cairo, Egypt. The specimen was first named by Fraas as ''Mesocetus schweinfurthi''. However, the name ''Mesocetus'' was previously used causing a change to the species name to ''Eocetus schweinfurthi''. Since the genus was first described in the early 20th century, several other specimens, mostly isolated vertebrae, have been attributed to ''Eocetus'', but the taxonomic status of these widely distributed specimens remain disputed. Discovery and taxonomy described "''Mesocetus schweinfurthi''" based on a dorsoventrally compressed skull with only I2 ''in situ'', a specimen supposedly originating from a 40 Ma Tethyan deposit at Mokattam. Fraas also referred two isolated teeth, P4 and M1, to the skull and the most important of his specimens is not the deformed skull, but the upper molar which retains three roots and a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basiloterus
''Basiloterus'' is an extinct genus of late-Eocene primitive whale from the Drazinda Formation, Pakistan and possibly also the Barton Group (originally Barton Beds) of England.Gingerich ''et al.'', 1997 ''Basiloterus husseini'' is the closest known relative of ''Basilosaurus'', but was not as large or elongated. The holotype is known from partial post cranial remains including two lumbar vertebrae. See also * Evolution of cetaceans The evolution of cetaceans is thought to have begun in the Indian subcontinent from even-toed ungulates 50 million years ago (mya) and to have proceeded over a period of at least 15 million years. Cetaceans are fully aquatic marine mammals bel ... References Bibliography * Basilosauridae Prehistoric cetacean genera Bartonian genera Eocene mammals of Asia Fossils of Pakistan Eocene mammals of Europe Fossils of England Fossil taxa described in 1997 {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosaurus
''Basilosaurus'' (meaning "king lizard") is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago (mya). First described in 1834, it was the first archaeocete and prehistoric whale known to science. Fossils attributed to the type species ''B. cetoides'' were discovered in the United States. They were originally thought to be of a giant reptile, hence the suffix "-saurus", Ancient Greek for "lizard". The animal was later found to be an early marine mammal, which prompted attempts at renaming the creature, which failed as the rules of zoological nomenclature dictate using the original name given. Fossils were later found of the second species, ''B. isis'', in 1904 in Egypt, Western Sahara, Morocco, Jordan, Tunisia, and Pakistan. Fossils have also been unearthed in the southeastern United States and Peru. ''Basilosaurus'' is considered to have been common in the Tethys Ocean. It was one of the largest, if not t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosaurinae
Basilosaurinae is a subfamily of cetaceans archaeocetes containing two genera: ''Basilosaurus'' and ''Basiloterus''.. Retrieved July 2013. They were characterized by elongated distal thoracic vertebrae, lumbar, and proximal sacrococcygeal. All known members of the subfamily are larger than their relatives of the Dorudontinae subfamily except ''Cynthiacetus''. Classification * Subfamily Basilosaurinae ** Genus ''Basilosaurus'' *** ''Basilosaurus cetoides'' *** ''Basilosaurus isis'' ** Genus ''Basiloterus ''Basiloterus'' is an extinct genus of late-Eocene primitive whale from the Drazinda Formation, Pakistan and possibly also the Barton Group (originally Barton Beds) of England.Gingerich ''et al.'', 1997 ''Basiloterus husseini'' is the closest k ...'' *** ''Basiloterus hussaini'' Notes References * * Basilosauridae Eocene first appearances Eocene extinctions {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosauridae
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.Buono M, Fordyce R.E., Marx F.G., Fernández M.S. & Reguero M. (2019). "Eocene Antarctica: a window into the earliest history of modern whales". ''Advances in Polar Science'' 30(3): p. 293-302. doi10.13679/j.advps.2019.0005/ref> The group is noted to be a paraphyletic assemblage of stem group whales from which the monophyletic Neoceti are derived. Characteristics Basilosaurids ranged in size from and were fairly similar to modern cetaceans in overall body form and function. Some genera tend to show signs of convergent evolution with mosasaurs by having long serpentine body shape, which suggests that this body plan seems to have been rather successful. Basilosaurid forelimbs have broad and fan-shaped scapulae attached to a humerus, radius, and ulna which are flatte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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