Ailuravus Temporal range: | |
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Ailuravus macrurus skeleton | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Rodentia |
Suborder: | Sciuromorpha |
Infraorder: | Protrogomorpha |
Family: | † Ischyromyidae |
Subfamily: | † Ailuravinae |
Genus: | † Ailuravus Rütimeyer, 1891 |
Species | |
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Ailuravus is a genus of prehistoric rodents in the family Ischyromyidae.
Ailuravus macrurus ("big-tailed cat-ancestor") was a primitive, squirrel-like rodent, one of the earliest known rodents, from the Messel pit Lagerstätte, in Germany. It lived during the Eocene period of Europe, in forests, and may have been arboreal. Furthermore, this species was discovered to have inhabited South Asia, specifically India. This was found through the comparison of the teeth found from each organism from both places. Due to this discovery, there is thought to be a connection between South Asia and Europe before they were separated and shifted into continents. In India, Ailuravus macrurus are thought to have inhabited the Cambay Basin, so they most likely preferred to live near aquatic regions along with fish species.
Perissodactyla is an order of ungulates. The order includes about 17 living species divided into three families: Equidae, Rhinocerotidae (rhinoceroses), and Tapiridae (tapirs). They typically have reduced the weight-bearing toes to three or one of the five original toes, though tapirs retain four toes on their front feet. The nonweight-bearing toes are either present, absent, vestigial, or positioned posteriorly. By contrast, artiodactyls bear most of their weight equally on four or two of the five toes: their third and fourth toes. Another difference between the two is that perissodactyls digest plant cellulose in their intestines, rather than in one or more stomach chambers as artiodactyls, with the exception of Suina, do.
The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae and the Ochotonidae (pikas). There are 110 recent species of lagomorph of which 109 are extant, including 10 genera of rabbits, 1 genus of hare and 1 genus of pika. The name of the order is derived from the Ancient Greek lagos + morphē.
Multituberculata is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, and reached a peak diversity during the Late Cretaceous and Paleocene. They eventually declined from the mid-Paleocene onwards, disappearing from the known fossil record in the late Eocene. They are the most diverse order of Mesozoic mammals with more than 200 species known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers. Multituberculates are usually placed as crown mammals outside either of the two main groups of living mammals—Theria, including placentals and marsupials, and Monotremata—but usually as closer to Theria than to monotremes. They are considered to be closely related to Euharamiyida and Gondwanatheria as part of Allotheria.
Viverravidae is an extinct monophyletic family of mammals from extinct superfamily Viverravoidea within the clade Carnivoramorpha, that lived from the early Palaeocene to the late Eocene in North America, Europe and Asia. They were once thought to be the earliest carnivorans and ancestral to extant ones, but now are placed outside the order Carnivora based on cranial morphology as relatives to extant carnivorans.
Miacidae is a former paraphyletic family of extinct primitive placental mammals that lived in North America, Europe and Asia during the Paleocene and Eocene epochs, about 65–33.9 million years ago. These mammals were basal to order Carnivora, the crown-group within the Carnivoraformes.
Chiropodomys is a genus of Old World rats and mice native to Southeast Asia and northeast India. They are tree-dwelling, very small mice, mostly found in tropical rainforest. In total six extant species have been identified, but only one of these, Chiropodomys gliroides, is common and widely distributed, and has been extensively studied.
Leontiniidae is an extinct family comprising eighteen genera of notoungulate mammals known from the Middle Eocene (Mustersan) to Late Miocene (Huayquerian) of South America.
Rhinotitan is an extinct genus of brontothere from the Eocene of Mongolia, where three species were described from the Shara Murun formation. The genus included medium to large brontotheres which had long skulls with nasal horns. Like other solid-horned brontotheres, Rhinotitan was sexually dimorphic in horn size. In living mammals, this pattern is found in species that live in groups; males have the larger horns, and use them in ritualized combats with other males to decide control of territories that offer breeding access to females. Most horned brontotheres had dish-shaped skulls assumed to be adapted for such combats. However, the skull of Rhinotitan was concave only near the front; the top and back of the skull was rounded in a way similar to hornless brontotheres. The functional significance of this character is unknown.
Eopelobates is an extinct genus of frogs in the family Pelobatidae. Closely related to the living European spadefoot toad, it is known from the Eocene of western North America, and the Eocene–Pliocene of Europe. It is suggested that the distribution over both Europe and North America is due to dispersal during the Paleocene-Eocene Thermal Maximum.
Charactosuchus is an extinct genus of crocodilian. It was assigned to the family Crocodylidae in 1988. Specimens have been found in Colombia, Brazil, Jamaica, and possibly Florida and South Carolina. It was gharial-like in appearance with its long narrow snout but bore no relation to them, being more closely related to modern crocodiles than to gharials.
Baenidae is an extinct family of paracryptodiran turtles known from the Early Cretaceous to Eocene of North America. While during the Early Cretaceous they are found across North America, during the Late Cretaceous they are only found in Laramidia, having disappeared from Appalachia. The majority of lineages survived the K-Pg Extinction, but the family was extinct by the latest Eocene. The name of the type genus, Baena, appears to be of Native American origin. They are primarily found in freshwater deposits, and are considered to be aquatic, with a largely generalist habit.
Zophotermes is an extinct genus of termite in the Isoptera family Rhinotermitidae known from two Eocene fossils found in India. The genus contains a single described species, Zophotermes ashoki placed in the subfamily Prorhinotermitinae.
Priscagamidae is an extinct family of iguanian lizards known from the Late Cretaceous of Mongolia and China and the Eocene of India, spanning a range from 83.6 to 48.6 million years ago. Probably the earliest priscagamids on indeterminate genera were found in Aptian-Albian sediments in "Hobur", Mongolia. It includes the genera Heterodontagama, Mimeosaurus, Phrynosomimus, Priscagama, and possibly Pleurodontagama. The first fossils of priscagamids were found in the Djadochta and Khermeen Tsav formations of Mongolia. More recently they have been found in the Cambay Formation in India, leading to the naming of Heterodontagama in 2013. Priscagamidae was originally described as a subfamily of Agamidae called Priscagaminae in 1984, but it was reclassified as a distinct family in 1989. Most phylogenetic analyses still find a close relationship between Priscagamidae and Agamidae, although a 2015 study found it to be basal to all other iguanian clades, warranting its removal from Iguania and placement in a larger clade called Iguanomorpha.
Neochoerus aesopi was a relatively large rodent species native to North America until their extinction about 12,000 years ago, being closely related to modern capybaras. It was part of the subfamily Hydrochoerinae. Fossils of it have been found in U.S. states such as Florida and South Carolina. The species was originally outlined in 1853, it weighed about 80 kg similar in size to the modern day capybara.
Palaeophasianus is an extinct genus of flightless Geranoididae birds that lived in North America during the Eocene period. Robert Wilson Shufeldt classified Palaeophasianus as a galliform when he described it in 1913. However it was transferred to Cracidae in 1964 by Pierce Brodkorb, while Joel Cracraft in 1968 placed it in Gruiformes.
Apatemys is a member of the family Apatemyidae, an extinct group of small and insectivorous placental mammals that lived in the Paleogene of North America, India, and Europe. While the number of genera and species is less agreed upon, it has been determined that two apatemyid genera, Apatemys and Sinclairella, existed sequentially during the Eocene in North America. The genus Apatemys, living as far back as 50.3 million years ago (mya), existed through part of the Wasatchian and persisted through the Duchesnean, and Sinclairella followed, existing from the Duchesnean through the Arikareean. Examinations of specimens belonging to the genus Apatemys suggest adaptations characteristic of arboreal mammals.
Sivacobus is an extinct species of antelope that lived in South Asia during the Plio-Pleistocene.
The Cambay Shale Formation is an Early Eocene-aged geologic formation in the Cambay Basin, India. It varies in thickness from a few meters on the margins of the basin to more than 2,500m in the depressions. It directly overlies the Olpad Formation and is, in turn, overlain by the Anklesvar Formation in the southern part of the basin and by Kalol Formation in the northern part of the basin. Further north, the Cambay Shale, in its lower part, is gradually replaced by tongues of paralic-deltaic Kadi Formation and finally by Tharad Formation.
Laomaki is a genus of adapiform primate that lived during the Early Oligocene in Asia, containing only the species Laomaki yunnanensis. It was described from a right maxilla fragment. Its molars and premolars are somewhat similar to those of Rencunius and Anthradapis respectively. Its placement within the family Sivaladapidae is uncertain; it has not been placed in a subfamily. It has been found at sites in Jammu and Kashmir and Yunnan, having lived around the time of the Eocene–Oligocene transition.