Parahippus leonensis
Encyclopedia
Parahippus leonensis is an extinct proto-horse
of the family Equidae
that was endemic to North America
during the Miocene
from 23.030—16.3 Ma living for approximately .
Parahippus leonensis was named for Leon or more specifically Leon County, Florida
.
in the Torreya Formation
of Florida. It was recombined as Hippodon leonensis by Quinn (1955); it was considered a nomen dubium by Macdonald (1992).
. Parahippus
means "side horse" and has been called the evolutionary link between the older forest
-dwelling horses and modern plain
s-dwelling grazers. It is believed to be a close relative to the group from which modern horses evolved. Side may refer to side branches on the posterior crest of the upper molar
s which separated Parahippus from Anchitherium
.
This genus of horses had a long head with eyes situated back from the middle of the skull. It had three toes, like other primitive horses, however Parahippus leonensis had smaller side toes. It was a common species from the Great Plains
to Florida
. Parahippus leonensis weighed in at about 72.5 Kg (160 pounds).
Parahippus leonensis was very likely the prey of Amphicyon
or Bear-dog, and dog-like Temnocyon.
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
of the family Equidae
Equidae
Equidae is the taxonomic family of horses and related animals, including the extant horses, donkeys, and zebras, and many other species known only from fossils. All extant species are in the genus Equus...
that was endemic to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
during the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
from 23.030—16.3 Ma living for approximately .
Parahippus leonensis was named for Leon or more specifically Leon County, Florida
Leon County, Florida
Leon County is a county located in the state of Florida, named after the Spanish explorer Juan Ponce de León. At the 2010 Census, the population was 275,487. The county seat of Leon County is Tallahassee which also serves as the state capital. The county seat is home to two of Florida's major...
.
Taxonomy
Parahippus leonensis was named by Sellards (1916). Its type specimen is FGS 5084. Its type locality is Griscom Plantation site, which is in a Miocene marine limestoneLimestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
in the Torreya Formation
Torreya Formation
The Torreya Formation is a Miocene geologic formation with an outcrop in North Florida. It is within the Hawthorn Group.-Age:Period: NeogeneEpoch: Early Miocene...
of Florida. It was recombined as Hippodon leonensis by Quinn (1955); it was considered a nomen dubium by Macdonald (1992).
Body mass
Two specimens were examined by M. Mendoza, C. M. Janis, and P. Palmqvist for body mass. The results were:- Specimen 1: 123.7 kg (272.7 lb)
- Specimen 2: 48.7 kg (107.4 lb)
Origin
Parahippus leonensis was the next step in evolution after MiohippusMiohippus
Miohippus was a genus of prehistoric horse existing longer than most Equidae. Miohippus lived in what is now North America during the Oligocene approximately 32-25 million years ago. While descending genera of this species lived during the Miocene period, the Miohippus was a horse of the Oligocene...
. Parahippus
Parahippus
Parahippus is an extinct relative of the modern horse, very similar to Miohippus, but slightly larger, at around tall, at the withers....
means "side horse" and has been called the evolutionary link between the older forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
-dwelling horses and modern plain
Plain
In geography, a plain is land with relatively low relief, that is flat or gently rolling. Prairies and steppes are types of plains, and the archetype for a plain is often thought of as a grassland, but plains in their natural state may also be covered in shrublands, woodland and forest, or...
s-dwelling grazers. It is believed to be a close relative to the group from which modern horses evolved. Side may refer to side branches on the posterior crest of the upper molar
Molar (tooth)
Molars are the rearmost and most complicated kind of tooth in most mammals. In many mammals they grind food; hence the Latin name mola, "millstone"....
s which separated Parahippus from Anchitherium
Anchitherium
Anchitherium was a fossil horse with a three-toed hoof.Anchitherium was a browsing horse that originated in the early Miocene of North America and subsequently dispersed to Europe and Asia, where it gave rise to the larger bodied genus Sinohippus...
.
This genus of horses had a long head with eyes situated back from the middle of the skull. It had three toes, like other primitive horses, however Parahippus leonensis had smaller side toes. It was a common species from the Great Plains
Great Plains
The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...
to Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
. Parahippus leonensis weighed in at about 72.5 Kg (160 pounds).
Parahippus leonensis was very likely the prey of Amphicyon
Amphicyon
Amphicyon is an extinct genus of large carnivorous bone-crushing mammals, known as bear-dogs, of the family Amphicyonidae, subfamily Amphicyoninae, from the Aquitanian Epoch until the Tortonian...
or Bear-dog, and dog-like Temnocyon.