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Stromerius
''Stromerius'' is an extinct genus of basilosaurid early whale known from the Late Eocene (Priabonian, ) of Fayum, Egypt (, paleocoordinates ). ''Stromerius'' is known from several well-preserved vertebrae. Distinguishing features for the genus include: long and forward-pointing metapophyses (bony processes) on the lumbar vertebrae; a relatively short lumbar spine with only twelve vertebrae of which four are interpreted as homologous to sacral vertebrae; one of the two thoracic vertebrae found has a dorsally-pointing neural spine interpreted as anticlinal (i.e. the spines of the other vertebrae are inclined towards this specific vertebra) which is a primitive retention in ''Stromerius'' not present in other basilosaurids. ''Stromerius'' is larger than the contemporary ''Saghacetus'' but smaller than the older ''Dorudon''. made ''S. nidensis'' the type species of the subfamily "Stromeriinae", but only mentioned this proposed subfamily briefly in his abstract. The genus is ... [...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] |
Archaeoceti
Archaeoceti ("ancient whales"), or Zeuglodontes in older literature, is a paraphyletic group of primitive cetaceans that lived from the Early Eocene to the late Oligocene (). Representing the earliest cetacean radiation, they include the initial amphibious stages in cetacean evolution, thus are the ancestors of both modern cetacean suborders, Mysticeti and Odontoceti. This initial diversification occurred in the shallow waters that separated India and Asia , resulting in some 30 species adapted to a fully oceanic life. Echolocation and filter-feeding evolved during a second radiation . All archaeocetes from the Ypresian (56–47.8 mya) and most from the Lutetian (47.8–41.3 mya) are known exclusively from Indo-Pakistan, but Bartonian (41.3–38.0 mya) and Priabonian (38.0–33.9 mya) genera are known from across Earth, including North America, Egypt, New Zealand, and Europe. Although no consensus exists regarding the mode of locomotion of which cetaceans were capable during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saghacetus
''Saghacetus'' is an extinct genus of basilosaurid early whale, fossils of which have been found in the Upper Eocene (middle Priabonian, ) Qasr el Sagha Formation, Egypt (, paleocoordinates ). In 1879, German botanist Georg August Schweinfurth spent many years exploring Africa and eventually discovered the first archaeocete whale in Egypt. He visited Qasr el Sagha in 1884 and 1886 and missed the now famous " Zeuglodon Valley" with a few kilometres. German palaeontologist Wilhelm Barnim Dames described the material, including a well-preserved dentary which is the type specimen of ''Zeuglodon osiris''. The generic name ''Saghacetus'' was established by to group the ancient species ''Dorudon osiris'', ''D. zitteli'', ''D. sensitivius'' and ''D. elliotsmithii'' on a single species, ''Saghacetus osiris''. This species is distinguished from other members of the subfamily Dorudontinae by its smaller size and the slightly elongated proximal lumbar and caudal vertebrae. ''Saghacet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen(s). Article 67.1 A similar concept is used for suprageneric groups and called a type genus. In botanical nomenclature, these terms have no formal standing under the code of nomenclature, but are sometimes borrowed from zoological nomenclature. In botany, the type of a genus name is a specimen (or, rarely, an illustration) which is also the type of a species name. The species name that has that type can also be referred to as the type of the genus name. Names of genus and family ranks, the various subdivisions of those ranks, and some higher-rank names based on genus names, have such types. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priabonian
The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between . The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of the Oligocene. Stratigraphic definition The Priabonian Stage was introduced in scientific literature by Ernest Munier-Chalmas and Albert de Lapparent in 1893. The stage is named after the small hamlet of Priabona in the community of Monte di Malo, in the Veneto region of northern Italy. The base of the Priabonian Stage is at the first appearance of calcareous nannoplankton species ''Chiasmolithus oamaruensis'' (which forms the base of nanoplankton biozone NP18). An official GSSP was ratified in 2020, and was placed in the Alano di Piave section in Alano di Piave, Belluno, Italy. The top of the Priabonian Stage (the base of the Rupelian Stage and Oligocene Series) is at the extinction of foram genus ''Hantkenina''. Sometimes local rock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fayum
Faiyum ( ar, الفيوم ' , borrowed from cop, ̀Ⲫⲓⲟⲙ or Ⲫⲓⲱⲙ ' from egy, pꜣ ym "the Sea, Lake") is a city in Middle Egypt. Located southwest of Cairo, in the Faiyum Oasis, it is the capital of the modern Faiyum Governorate. Originally called Shedet in Egyptian, the Greeks called it in grc-koi, Κροκοδειλόπολις, Krokodilópolis, and later grc-byzantine, Ἀρσινόη, Arsinoë. It is one of Egypt's oldest cities due to its strategic location. Name and etymology Originally founded by the ancient Egyptians as Shedet, its current name in English is also spelled as Fayum, Faiyum or Al Faiyūm. Faiyum was also previously officially named Madīnet Al Faiyūm (Arabic for ''The City of Faiyum''). The name Faiyum (and its spelling variations) may also refer to the Faiyum Oasis, although it is commonly used by Egyptians today to refer to the city. The modern name of the city comes from Coptic / ' (whence the proper name '), meaning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metapophysis
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch (in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar Vertebra
The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse process (since it is only found in the cervical region) and by the absence of facets on the sides of the body (as found only in the thoracic region). They are designated L1 to L5, starting at the top. The lumbar vertebrae help support the weight of the body, and permit movement. Human anatomy General characteristics The adjacent figure depicts the general characteristics of the first through fourth lumbar vertebrae. The fifth vertebra contains certain peculiarities, which are detailed below. As with other vertebrae, each lumbar vertebra consists of a ''vertebral body'' and a ''vertebral arch''. The vertebral arch, consisting of a pair of ''pedicles'' and a pair of ''laminae'', encloses the ''vertebral foramen'' (opening) and sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Spine
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch (in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticlinal
{{disambig ...
Anticlinal may refer to: *Anticline, in structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. *Anticlinal, in stereochemistry, a torsion angle between 90° to 150°, and –90° to –150°; see Alkane_stereochemistry See also *Weald–Artois Anticline * Mareuil Anticline * La Tour-Blanche Anticline *Usk Anticline *Fold (geology) *Detachment fold *Stereochemistry Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorudon
''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] |
.JPEG/1200px-Zeuglodon_osiris_dentary_(Dames1894).JPEG "Click for more on -> Saghacetus")
_(2).jpg "Click for more on -> Type Species")
