Epihippus Early | |
---|---|
Illustration of Epihippus gracilis skull and teeth | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Perissodactyla |
Family: | Equidae |
Genus: | † Epihippus Marsh, 1877 |
Synonyms | |
|
Epihippus is an extinct genus of the modern horse family Equidae that lived in the Eocene, from 46 to 38 million years ago.
Epihippus is believed to have evolved from Orohippus , which continued the evolutionary trend of increasingly efficient grinding teeth. It had five grinding, low-crowned cheek teeth with well-formed crests. A late and partially recognized species of Epihippus, sometimes called Duchesnehippus intermedius, had teeth similar to Oligocene equids, although slightly less developed. The genus fed mostly on insects, berries and plant material. [2] [3]
There are three species: [1]
Equidae is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. The family evolved around 50 million years ago from a small, multi-toed ungulate into larger, single-toed animals. All extant species are in the genus Equus, which originated in North America. Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and several extinct families. It is more specifically grouped within the superfamily Equoidea, the only other family being the extinct Palaeotheriidae.
Carcharodon is a genus of sharks within the family Lamnidae, colloquially called the "white sharks." The only extant member is the great white shark. The extant species was preceded by a number of fossil (extinct) species including C. hubbelli and C. hastalis. The first appearance of the genus may have been as early as the Early Miocene or Late Oligocene. Carcharocles megalodon is still argued by some paleontologists to be a close relative of Carcharodon carcharias - as well as being in the same genus. The megalodon's scientific name was originally "Carcharodon" megalodon, but more recently, the giant shark has been assigned by most scientists to either the genus Carcharocles or Otodus.
Mesohippus is an extinct genus of early horse. It lived 37 to 32 million years ago in the Early Oligocene. Like many fossil horses, Mesohippus was common in North America. Its shoulder height is estimated at 60 cm.
Sand sharks, also known as sand tiger sharks, gray nurse sharks or ragged tooth sharks, are mackerel sharks of the family Odontaspididae. They are found worldwide in temperate and tropical waters. The three species are in two genera.
Zapodidae, the jumping mice, is a family of mouse-like rodents in North America and China.
Arctocyon is an extinct genus of ungulate mammals. Arctocyon was a "ground dwelling omnivore", that lived from 61.3-56.8 Ma. Synonyms of Arctocyon include Claenodon, and Neoclaenodon. Arctocyon was likely plantigrade, meaning that it walked with its feet flat on the ground, rather than on its toes.
Latimeriidae is the only extant family of coelacanths, an ancient lineage of lobe-finned fish. It contains two extant species in the genus Latimeria, found in deep waters off the coasts of southern Africa and east-central Indonesia. In addition, several fossil genera are known from the Mesozoic of Europe, the Middle East, and the southeastern United States, dating back to the Triassic.
The evolution of the horse, a mammal of the family Equidae, occurred over a geologic time scale of 50 million years, transforming the small, dog-sized, forest-dwelling Eohippus into the modern horse. Paleozoologists have been able to piece together a more complete outline of the evolutionary lineage of the modern horse than of any other animal. Much of this evolution took place in North America, where horses originated but became extinct about 10,000 years ago, before being reintroduced in the 15th century.
Ganorhynchus is an extinct genus of prehistoric lungfish from the Devonian period. Fossils were found in Mansfield, Pennsylvania.
Euthynotus is an extinct genus of prehistoric bony fish that lived during the early Toarcian stage of the Early Jurassic epoch. It is generally considered the basalmost pachycormiform.
Yacarerani is an extinct genus of Late Cretaceous notosuchian crocodylomorph. Fossils have been found in 2002 in the Cajones Formation in Amboró National Park of central Bolivia and are Turonian-Santonian in age. The genus was described in 2009 in the Journal of Vertebrate Paleontology. The material represents two individuals and was found in association with eggs that are thought to have been part of a nest. Yacarerani was a small crocodylomorph at around 80 centimetres (31 in) in length. It may have lived in small groups, creating burrows to lay eggs in.
Chelonoidis is a genus of turtles in the tortoise family erected by Leopold Fitzinger in 1835. They are found in South America and the Galápagos Islands, and formerly had a wide distribution in the West Indies.
Listriodon is an extinct genus of pig-like animals that lived in Eurasia during the Miocene.
Galeocerdo alabamensis is an extinct relative of the modern tiger shark. Nomenclature of this shark has been debated, and recent literature identified it more closely with the Physogaleus genus of prehistoric shark, rather than Galeocerdo. The classification of Physogaleus is known as tiger-like sharks while Galeocerdo refers to tiger sharks. In 2003, P. alabamensis was classified as Galeocerdo. However, in 2019, they were proclaimed to be more morphologically similar to the genus Physogaleus. This definition was based primarily on tooth shape, as the majority of information on P. alabamensis is a result of studying tooth fossils. Distinctions between Physogaleus and Galeocerdo are difficult with extinct sharks from the Oilgocene/Miocene as there is little paleobiological information allowing for hard conclusions.
Boreostemma is an extinct genus of glyptodonts from northern South America. Fossils assigned to the genus were first described as belonging to Asterostemma from southern South America, but have been placed in the new genus Boreostemma by Carlini et al. in 2008. The type species is B. pliocena. Fossils of Boreostemma have been found in the Honda Group of Colombia, in Peru and Venezuela.
Annea is an extinct genus of carpet shark from the middle Jurassic epoch of the Jurassic period. It is currently known by two species. A. carinata is known from the upper Aalenian and lower Bajocian of Germany. A. maubeugei is known from the middle Toarcian of Belgium. Its name honors Dr. P. L. Maubeuge, who studied the Jurassic of Lorraine in which this species was found. This genus appears to exhibit heterodonty.
Azabbaremys is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Teberemt Formation of Mali. It was described in 2001, based on a skull that had been recovered in an expedition in 1981. The genus consists solely of the type species Azabbaremys moragjonesi. The genus name is derived from Azabbar, a monster in Tamasheq folk stories. The species is named for Morag Jones, a research student who participated in the discovery of the specimen and died in the expedition. Azabbaremys is most closely related to another Paleocene side-necked turtle, Acleistochelys.
Cockerellites is a genus of extinct temperate bass described from early Eocene-aged fossils found in the Green River Formation of Wyoming. It is characterized by a sunfish-like body and its stout dorsal and anal spines. The type species, C. liops, was originally named as a species of Priscacara by Edward Drinker Cope upon creating the genus in 1877, but P. liops was moved to the newly created genus Cockerellites by D. Jordan and H. Hanibal in 1923. Some authors, such as Whitlock (2010), still consider Cockerellites liops as a species of Priscacara.
Phenacomyini is a tribe of voles in the subfamily Arvicolinae. It contains five species in two genera, all of which are found in North America.