| Aegyptocetus | |
|---|---|
 | |
| Reconstructed skull | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Infraorder: | Cetacea |
| Family: | † Protocetidae |
| Genus: | † Aegyptocetus Bianucci & Gingerich 2011 |
| Species: | †A. tarfa |
| Binomial name | |
| †Aegyptocetus tarfa | |
Aegyptocetus is an extinct genus of protocetid archaeocete whale known from Egypt. [1]
Aegyptocetus is known from the articulated holotype MSNTUP I-15459, an almost complete cranium, lower jaws (with teeth) and a partial postcranial skeleton (cervical and thoracic vertebrae and ribs). The specimen was recovered when marbleized limestone was imported commercially to Italy. It was collected in the Khashm el-Raqaba limestone quarry ( 28°30′N31°48′E / 28.5°N 31.8°E , paleocoordinates 22°54′N27°12′E / 22.9°N 27.2°E ) [2] from the Gebel Hof Formation on the northern flank of Wadi Tarfa in the Eastern Desert of Egypt, dating to the late Mokattamian age of the middle Eocene, about 41 to 40 million years ago . Its cause of death may have been an attack by a large shark as pattern of shark tooth marks preserved on the ribs. [1]
Aegyptocetus was first named by Giovanni Bianucci and Philip D. Gingerich in 2011 and the type species is Aegyptocetus tarfa. The generic name is derived from Aegyptus, Latin for Egypt, and cetus, Latin for whale. The specific name refers to Wadi Tarfa, the desert valley where the holotype was found. [1]
Aegyptocetus had features in its cranium and dentaries adapted for hearing in water. Its thoracic vertebrae (T1–T8), however, had long neural spines which is a characteristic of the weight-bearing system of land-living mammals retained in protocetids, such as Rodhocetus and Qaisracetus , but absent in the more derived basilosaurids, such as Dorudon . This suggests that Aegyptocetus, like other protocetids, was able to support its body on land and probably was semi-aquatic. [3]
Rodhocetus is an extinct genus of protocetid early whale known from the Lutetian of Pakistan. The best-known protocetid, Rodhocetus is known from two partial skeletons that taken together give a complete image of an Eocene whale that had short limbs with long hands and feet that were probably webbed and a sacrum that was immobile with four partially fused sacral vertebrae. It is one of several extinct whale genera that possess land mammal characteristics, thus demonstrating the evolutionary transition from land to sea.
Ambulocetus is a genus of early amphibious cetacean from the Kuldana Formation in Pakistan, roughly 48 or 47 million years ago during the Early Eocene (Lutetian). It contains one species, Ambulocetus natans. Ambulocetus is known primarily from a single skeleton which is about 80% complete, and is among the most completely known Eocene cetaceans, instrumental in the study of cetacean evolution and the transition from land to sea. It had four functional limbs, and was the first cetacean discovered preserving a suite of adaptations consistent with an amphibious lifestyle. Ambulocetus is classified in the group Archaeoceti—the ancient forerunners of modern cetaceans whose members span the transition from land to sea—and in the family Ambulocetidae, which includes Himalayacetus and Gandakasia.
Basilosaurus 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 zoological nomenclature dictates using the original name given. Fossils were later found of the second species, B. isis, in 1904 in Egypt, Morocco, Jordan, Tunisia, and Pakistan. Basilosaurus has a possible record in Seymour Island in Antarctica as well.
Basilosauridae is a paraphyletic 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.
Wādī al-Ḥītān is a paleontological site in the Faiyum Governorate of Egypt, some 150 kilometres (93 mi) south-west of Cairo. It was designated a UNESCO World Heritage Site in July 2005 for its hundreds of fossils of some of the earliest forms of whale, the archaeoceti. The site reveals evidence for the explanation of one of the greatest mysteries of the evolution of whales: the emergence of the whale as an ocean-going mammal from a previous life as a land-based animal. No other place in the world yields the number, concentration and quality of such fossils, as is their accessibility and setting in an attractive and protected landscape. The valley was therefore inscribed on the UNESCO World Heritage List in 2005.
Archaeoceti, 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 53 to 45 mya, resulting in some 30 species adapted to a fully oceanic life; though both echolocation and filter-feeding evolved during a second radiation 36 to 35 mya.
Protocetus atavus is an extinct species of primitive cetacean from Egypt. It lived during the middle Eocene period 45 million years ago. The first discovered protocetid, Protocetus atavus was described by Fraas 1904 based on a cranium and a number of associated vertebrae and ribs found in middle Lutetian Tethyan marine limestone from Gebel Mokattam near Cairo, Egypt.
Remingtonocetidae is a diverse family of early aquatic mammals of the order Cetacea. The family is named after paleocetologist Remington Kellogg.
Gaviacetus is an extinct archaeocete whale that lived approximately 45 million years ago. Gaviacetus was named for its characteristic narrow rostrum and the fast pursuit predation suggested by its unfused sacral vertebrae.
Ancalecetus is an extinct genus of early whale known from the Late Eocene Birket Qarun Formation in Wadi Al-Hitan, Egypt. The species is named after anthropologist and primate researcher Elwyn L. Simons who discovered the type specimen in 1985.
Chrysocetus is a genus of extinct early whale known from Late Eocene-aged fossils of the eastern United States and western Africa.
The Qasr el Sagha Formationis a geological formation located in Egypt The formation is part of the Wadi El Hitan World Heritage Site. The Qasr el Sagha Formation overlies the Birket Qarun Formation and is overlain by the Gebel Qatrani Formation. The sandstones and shales of the formation were deposited in a deltaic to shallow marine environment. It dates to the Late Eocene.
Protocetidae, the protocetids, form a diverse and heterogeneous group of extinct cetaceans known from Asia, Europe, Africa, South America, and North America.
Stromerius is an extinct genus of basilosaurid early whale known from the Late Eocene of Fayum, Egypt.
Natchitochia is an extinct protocetid early whale known from the Middle Eocene Cook Mountain Formation in Natchitoches Parish, Louisiana.
Qaisracetus is an extinct protocetid early whale known from the Eocene of Baluchistan, Pakistan.
Carolinacetus is an extinct protocetid early whale found in the Bartonian Tupelo Bay Formation in Berkeley County, South Carolina.
Eocetus is an extinct protocetid early whale known from the early late Eocene Giushi Formation in Gebel Mokattam, 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.
Aegicetus is an extinct genus of protocetid whale based on a partial skull with much of an associated postcranial skeleton discovered in Egypt. It lived around 35 million years ago, making it the youngest known protocetid to date. Aegicetus was discovered in 2007 at Wadi El Hitan as a relatively complete skeleton and a partial second specimen. They were assigned to a new genus and species in 2019 by Philip D. Gingerich et al.
Phiomicetus is a genus of protocetid whale that lived between 43 and 42 million years ago during the middle Eocene in what is now Egypt. It had powerful jaws and large teeth that would have allowed it to hunt and tear large prey.
Archaeocete genera by family | |||||||
|---|---|---|---|---|---|---|---|
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| Pakicetidae | |||||||
| Ambulocetidae | |||||||
| Remingtonocetidae | |||||||
| Protocetidae |
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| Basilosauridae |
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