The Eocene is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek Ἠώς and καινός and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.
Podocnemididae is a family of pleurodire (side-necked) turtles, once widely distributed. Most of its 41 genera and 57 species are now extinct. Seven of its eight surviving species are native to South America: the genus Peltocephalus, with two species, only one of which is extant ; and the genus Podocnemis, with six living species of South American side-necked river turtles and four extinct. There is also one genus native to Madagascar: Erymnochelys, the Madagascan big-headed turtle, whose single species E. madagascariensis.
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 southeastern 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, prompting attempts at renaming the creature, which failed as the rules of zoological nomenclature dictate using the original name given. The second species named in 1904, B. isis, lived in the region currently known as the Mediterranean Sea, with fossils found in North Africa and Jordan.
Basilosauridae is a family of extinct cetaceans that lived during the middle to late Eocene. Basilosaurids are known from all continents including Antarctica, and are 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.
A nummulite is a large lenticular fossil, characterised by its numerous coils, subdivided by septa into chambers. They are the shells of the fossil and present-day marine protozoan Nummulites, a type of foraminiferan. Nummulites commonly vary in diameter from 1.3 cm to 5 cm and are common in Eocene to Miocene marine rocks, particularly around southwest Asia and the Mediterranean in the area that once constituted the Tethys Ocean, such as Eocene limestones from Egypt or from Pakistan. Fossils up to six inches wide are found in the Middle Eocene rocks of Turkey. They are valuable as index fossils.
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. Echolocation and filter-feeding evolved during a second radiation 36 to 35 mya.
Oligopithecidae is an extinct basal Catarrhine family from the late Eocene of Egypt as sister of the rest of the Catarrhines. Its members were probably insectivorous, due to their simple molars and cusp arrangement.
Bothremydidae is an extinct family of side-necked turtles (Pleurodira) known from the Cretaceous and Cenozoic. They are closely related to Podocnemididae, and are amongst the most widely distributed pleurodire groups, with their fossils having been found in Africa, India, the Middle East, Europe, North America and South America. Bothremydids were aquatic turtles with a high morphological diversity, indicative of generalist, molluscivorous, piscivorous and possibly herbivorous grazing diets, with some probably capable of suction feeding. Unlike modern pleurodires, which are exclusively freshwater, bothremydids inhabited freshwater, marine and coastal environments. Their marine habits allowed bothremydids to disperse across oceanic barriers into Europe and North America during the early Late Cretaceous (Cenomanian). The youngest records of the group are indeterminate remains from Saudi Arabia and Oman, dating to the Miocene.
Eotheroides is an extinct genus of Eocene sirenian. It is an early member of the family Dugongidae, which includes the extant dugong. Fossils have been found from Egypt, India, and Madagascar. Eotheroides was first described by Richard Owen in 1875 under the name Eotherium, which was replaced by the current name in 1899.
Karanisia is an extinct genus of strepsirrhine primate from middle Eocene deposits in Egypt.
The Jebel Qatrani Formation is a geologic formation located in the Faiyum Governorate of central Egypt. It is exposed between the Jebel Qatrani escarpment and the Qasr el Sagha escarpment, north of Birket Qarun lake near Faiyum. The formation conformably overlies the Qasr el Sagha Formation and is topped by the Widan el Faras Basalt. The age of the formation has been subject to debate, but the most recent research indicates that it covers both the latest parts of the Eocene and the Early Oligocene, spanning over the boundary between these two time periods.
Nosmips aenigmaticus is a rare fossil primate known only from 12 teeth. Most teeth were found at a site in the Fayum Depression about 40 miles (64 km) outside Cairo, Egypt.
Aegyptocetus is an extinct genus of protocetid archaeocete whale known from Egypt.
Cordichelys is an extinct genus of podocnemidid turtle. It was around during the Eocene. Fossils of this turtle have been discovered at Wadi El Hitan as of November 2020.
Masracetus is an extinct genus of basilosaurid ancient whale known from the Late Eocene of Egypt.
Eocetus is an extinct protocetid early whale known from the early-late Eocene Giushi Formation in Gebel Mokattam, outside Cairo, Egypt. Fossil remains have also been discovered in the Aridal Formation of the Sahara Desert in southwestern Morocco.
Parapithecoidea is an extinct superfamily of primates which lived in the Eocene and Oligocene periods in Egypt. In some classifications all Parapithecoidea are placed within the family Parapithecidae. Seiffert et al. (2010) propose that Parapithecoidea arose during the Bartonian, with a split between Biretia and the Parapithecidae occurring early in the Priabonian.
Proteopithecidae is an extinct family of primates which lived in the Priabonian and probably early Oligocene periods. Fossils that have been found are in the Jebel Qatrani Formation in Egypt. Currently two genera are recognised, each with a single species, those being Proteopithecus sylviae and Serapia eocaena.
Hesham Sallam is an Egyptian paleontologist and the founder of the Mansoura University Vertebrate Paleontology Center (MUVP-C), the first vertebrate paleontology program in the Middle East. He works as an associate professor at the American University in Cairo and Mansoura University. Sallam led the discovery and description of Mansourasaurus shahinae, a species of sauropod dinosaur from Egypt, which has improved understanding of the prehistory of Africa during the latest Cretaceous period. His work has helped popularize paleontology in Egypt.
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.
