A mastodon is a member of the genus Mammut, which, strictly defined, was endemic to North America and lived from the late Miocene to the early Holocene. Mastodons belong to the order Proboscidea, the same order as elephants and mammoths. Mammut is the type genus of the extinct family Mammutidae, which diverged from the ancestors of modern elephants at least 27–25 million years ago, during the Oligocene.
Mammutidae is an extinct family of proboscideans belonging to Elephantimorpha. It is best known for the mastodons, which inhabited North America from the Late Miocene until their extinction at beginning of the Holocene, around 11,000 years ago. The earliest fossils of the group are known from the Late Oligocene of Africa, around 24 million years ago, and fossils of the group have also been found across Eurasia. The name "mastodon" derives from Greek, μαστός "nipple" and ὀδούς "tooth", referring to their characteristic teeth.
Moeritherium is an extinct genus of basal proboscideans from the Eocene of North and West Africa. It was related to elephants and, more distantly, to sea cows and hyraxes.
Arsinoitherium is an extinct genus of paenungulate mammals belonging to the extinct order Embrithopoda. It is related to elephants, sirenians, and hyraxes. Arsinoitheres were superficially rhinoceros-like herbivores that lived during the Late Eocene and the Early Oligocene of North Africa from 36 to 30 million years ago, in areas of tropical rainforest and at the margin of mangrove swamps. A species described in 2004, A. giganteum, lived in Ethiopia about 27 million years ago.
Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch. The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed.
The genus Apidium is that of at least three extinct primates living in the early Oligocene, from 30 to 28 million years ago. Apidium fossils are common in the Fayoum deposits of Egypt. Fossils of the earlier species, Apidium moustafai, are rare; fossils of the later species Apidium phiomense are fairly common.
Pyrotherium is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina and Bolivia, during the Late Oligocene. It was named Pyrotherium because the first specimens were excavated from an ancient volcanic ash deposit. Fossils of the genus have been found in the Deseado and Sarmiento Formations of Argentina and the Salla Formation of Bolivia.
Numidotheriidae is an extinct family of primitive proboscideans that lived from the late Paleocene to the early Oligocene periods of North Africa.
Barytherium is a genus of an extinct family (Barytheriidae) of primitive proboscideans that lived during the late Eocene and early Oligocene in North Africa. The type species is Barytherium grave, found at the beginning of the 20th century in Fayum, Egypt. Since then, more complete specimens have been found at Dor el Talha, Libya. More fossils were also discovered in 2011 in the Aidum area in Dhofar by Oman's Ministry of Heritage and Culture, which was named Barytherium omansi.
Eritreum melakeghebrekristosi is an extinct species of proboscidean mammal, which lived in Northeast Africa during the late Oligocene some 27 million years ago, and is considered to be the missing link between modern elephants and their ancestors. The fossils of this species are the oldest known fossils featuring the horizontal tooth displacement seen in modern elephants. The species is estimated to have weighed 484 kg (1,067 lb) and stood about 1.3 m (4.3 ft) at the shoulder, much smaller than modern species.
Barytheriidae is an extinct family of primitive proboscideans that lived during the late Eocene and early Oligocene in North Africa and Oman. The Barytheriidae were the first large-sized proboscideans to appear in the fossil record and were characterized by a strong sexual dimorphism.
Palaeomastodon is an extinct genus within the elephant order Proboscidea. Its fossils have been extracted from Oligocene strata conventionally dated to 33.9-23.03 million years old. Usually considered an ancestor or near-ancestor of elephants or mastodons as a member of Elephantiformes it lived in marshes and fluvial-deltaic environments of what is now Egypt, Ethiopia, Libya, and Saudi Arabia.
Eogavialis is an extinct genus of eusuchian crocodylomorph, usually regarded as a gavialoid crocodylian. It superficially resembles Tomistoma schlegelii, the extant false gharial, and consequently material from the genus was originally referred to Tomistoma. Indeed, it was not until 1982 that the name Eogavialis was constructed after it was realised that the specimens were from a more basal form.
Saadanius is a genus of fossil primates dating to the Oligocene that is closely related to the common ancestor of the Old World monkeys and apes, collectively known as catarrhines. It is represented by a single species, Saadanius hijazensis, which is known only from a single partial skull tentatively dated between 29 and 28 million years ago. It was discovered in 2009 in western Saudi Arabia near Mecca and was first described in 2010 after comparison with both living and fossil catarrhines.
Astorgosuchus is an extinct monospecific genus of crocodilian, closely related to true crocodiles, that lived in Pakistan during the late Oligocene period. This crocodile may have reached lengths of up to 7–8 m (23–26 ft) and is known to have preyed on many of the large mammals found in its environment. Bite marks of a large crocodile have been found on the bones of juvenile Paraceratherium, however if these were left by Astorgosuchus cannot be said with certainty. The genus contains a single species, Astorgosuchus bugtiensis, which was originally named as a species of Crocodylus in 1908 and was moved to its own genus in 2019.
Propliopithecoidea is a superfamily of catarrhine primates that inhabited Africa and the Arabian Peninsula during the Early Oligocene about 32 to 29 million years ago. Fossils have been found in Egypt, Oman and Angola. They are one of the earliest known families of catarrhines. They have a number of features in common with extant catarrhines, but also features that are primitive and not found in later catarrhine families.
Dzungariotherium is a genus of paraceratheriid, an extinct group of large, hornless rhinocerotoids, which lived during the middle and late Oligocene of northwest China. The type species D. orgosense was described in 1973 based on fossils—mainly teeth—from Dzungaria in Xinjiang, northwest China.
Paulogervaisia is an extinct genus of mammal, belonging to the family Didolodontidae. Its fossilized remains have been found in South America.
Baguatherium is an extinct genus of herbivorous mammal, belonging to the order Pyrotheria. It lived during the Early Oligocene, and its fossilized remains were discovered in Peru.
Dagbatitherium is an extinct genus of proboscideans. So far a single molar from the phosphate basins of Togo in West Africa has been found. The fossil dates to the Middle Eocene, around 47 million years ago. A striking feature of the tooth are the three pairs of cusps oriented transversely to the longitudinal axis of the tooth. This feature is found in more derived proboscideans, which are grouped in the Elephantiformes. For its age, Dagbatitherium is the earliest member of Elephantiformes to date. Furthermore, it is characterized by a low tooth crown and a humped occlusal pattern. The genus was described in 2021.
