| Thadanius Temporal range: Late Oligocene ~ | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | † Litopterna |
| Family: | † Adianthidae |
| Subfamily: | † Adianthinae |
| Genus: | † Thadanius Cifelli & Soria 1983 |
| Type species | |
| Thadanius hoffstetteri Cifelli & Soria, 1983 | |
| Species | |
| |
Thadanius is an extinct genus of Litoptern, belonging to the family Adianthidae. It lived during the Late Oligocene, in what is today Bolivia. [1]
Only known from the fossilized remains of its mandible and teeth, this animal may have been similar to its relatives Adianthus and Adiantoides , and probably was a small animal, the size of a small dog and slender in build. Thadanius was characterized by moderately high crowned teeth ; the lower molars were devoid of anterior cingulum, while the hypoconulid was not expanded as in other contemporary Adianthidae, such as Tricoelodus and Proadiantus to form a third lobe on the third molar. The entoconid did not reach the apex of the hypoconulid, but was connected to an hypoconulid-entoconid crest, and a rudimentary entolophid was present, especially on the third lower molar. There was no basin on the lower third molar. [1]
Thadanius was a member of the Adianthidae, a clade of small-sized litopterns that went extinct during the Miocene period. Thadanius shares similarities with Proadiantus, and they may have been related, as Tricoelodus. [1]
Thadanius was first described in 1983, based on fragmentary remains from the Salla Formation, in the Loayza Province of Bolivia, in terrains dated from the Late Oligocene. Its name is an anagram of Adianthus, the eponymous genus of Adianthidae. [1]
Leptictidium is an extinct genus of small mammals that were likely bipedal. Comprising eight species, they resembled today's bilbies, bandicoots, and elephant shrews. They are especially interesting for their combination of characteristics typical of primitive eutherians with highly specialized adaptations, such as powerful hind legs and a long tail which aided in locomotion. They were omnivorous, their diet a combination of insects, lizards and small mammals. Lepticidium and other lepticids are not placentals, but are non-placentral eutherians, although closely related. They appeared in the Lower Eocene, a time of warm temperatures and high humidity, roughly fifty million years ago. Although they were widespread throughout Europe, they became extinct around thirty-five million years ago with no descendants, probably because they were adapted to live in forest ecosystems and were unable to adapt to the open plains of the Oligocene.
Litopterna is an extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of South American ungulates that were endemic to the continent, until the Great American Biotic Interchange brought new ungulate species. Like other endemic South American mammals, their relationship to other mammal groups had long been unclear, but recent genetic and proteomic evidence indicates that their closest living relatives are Perissodactyls including horses, rhinoceros, and tapirs, and that litopterns are closely related to notoungulates, another widespread group of South American ungulates.
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 Sarmiento Formation of Argentina and the Salla Formation of Bolivia.
Dermotherium is a genus of fossil mammals closely related to the living colugos, a small group of gliding mammals from Southeast Asia. Two species are recognized: D. major from the Late Eocene of Thailand, based on a single fragment of the lower jaw, and D. chimaera from the Late Oligocene of Thailand, known from three fragments of the lower jaw and two isolated upper molars. In addition, a single isolated upper molar from the Early Oligocene of Pakistan has been tentatively assigned to D. chimaera. All sites where fossils of Dermotherium have been found were probably forested environments and the fossil species were probably forest dwellers like living colugos, but whether they had the gliding adaptations of the living species is unknown.
Afrasia djijidae is a fossil primate that lived in Myanmar approximately 37 million years ago, during the late middle Eocene. The only species in the genus Afrasia, it was a small primate, estimated to weigh around 100 grams (3.5 oz). Despite the significant geographic distance between them, Afrasia is thought to be closely related to Afrotarsius, an enigmatic fossil found in Libya and Egypt that dates to 38–39 million years ago. If this relationship is correct, it suggests that early simians dispersed from Asia to Africa during the middle Eocene and would add further support to the hypothesis that the first simians evolved in Asia, not Africa. Neither Afrasia nor Afrotarsius, which together form the family Afrotarsiidae, is considered ancestral to living simians, but they are part of a side branch or stem group known as eosimiiforms. Because they did not give rise to the stem simians that are known from the same deposits in Africa, early Asian simians are thought to have dispersed from Asia to Africa more than once prior to the late middle Eocene. Such dispersals from Asia to Africa also were seen around the same time in other mammalian groups, including hystricognathous rodents and anthracotheres.
Indraloris is a fossil primate from the Miocene of India and Pakistan in the family Sivaladapidae. Two species are now recognized: I. himalayensis from Haritalyangar, India and I. kamlialensis from the Pothohar Plateau, Pakistan. Other material from the Potwar Plateau may represent an additional, unnamed species. Body mass estimates range from about 2 kg (4.4 lb) for the smaller I. kamlialensis to over 4 kg (8.8 lb) for the larger I. himalayensis.
Llullataruca is an extinct genus of litoptern mammal belonging to the family Macraucheniidae. It lived during the Middle Miocene. Its fossil remains have been found in Bolivia.
Paulogervaisia is an extinct genus of mammal, belonging to the family Didolodontidae. Its fossilized remains have been found in South America.
Notoetayoa is an extinct genus of mammal, from the order Xenungulata. It contains a single species, Notoetayoa gargantuai, which lived during the Middle Paleocene. Its fossilized remains were discovered in South America.
Adianthus is an extinct genus of Litoptern. It lived during the Early Miocene, in what is now Argentina.
Proadiantus is an extinct genus of herbivorous mammal, belonging to the order Litopterna. It lived during the Late Oligocene, in what is today South America.
Adiantoides is an extinct genus of herbivorous mammal, belonging to the order Litopterna. It lived during the Middle to Late Eocene, in South America.
Proectocion is an extinct genus of herbivorous mammal, belonging to the order Litopterna. It lived during the Early Eocene, in what is now South America.
Protheosodon is an extinct genus of proterotheriid litoptern. It lived from the Late Oligocene to the Early Miocene in what is now Argentina and Colombia.
Prolicaphrium is an extinct genus of litoptern belonging to the family Proterotheriidae. It lived during the Early Miocene, in what is now [Argentina]].
Anayatherium is an extinct genus of notoungulate belonging to the family Leontiniidae. It lived during the Late Oligocene, and its fossilized remains were discovered in South America.
Sallatherium is an extinct genus of Notoungulate, belonging to the suborder Typotheria; It lived during the Late Oligocene, and its fossilized remains were discovered in South America.
Holoclemensia is an extinct genus of mammal of uncertain phylogenetic placement. It lived during the Early Cretaceous and its fossil remains were discovered in Texas.
Asiatherium is an extinct genus of mammal, probably belonging to Metatheria. It lived during the Late Cretaceous, and its fossilized remains were discovered in Mongolia.
Fredszalaya is an extinct genus of omnivorous mammal, belonging to the order Sparassodonta. It lived during the Late Oligocene, and its fossilized remains were discovered in South America.
