Parahippus leonensis

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 6.73 million years.^[1]

Parahippus leonensis was named for Leon or more specifically Leon County, Florida.^[2]

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 limestone in the Torreya Formation of Florida. It was recombined as Hippodon leonensis by Quinn (1955); it was considered a nomen dubium by Macdonald (1992).^[3]

Morphology

Body mass

Two specimens were examined by M. Mendoza, C. M. Janis, and P. Palmqvist for body mass.^[4] The results were:

• Specimen 1: 123.7 kg (270 lb)
• Specimen 2: 48.7 kg (110 lb)

Origin

Parahippus leonensis was the next step in evolution after Miohippus. Parahippus means "side horse" and has been called the evolutionary link between the older forest-dwelling horses and modern plains-dwelling grazers. It is believed to be a close relative to the group from which modern horses evolved.^[5][6] Side may refer to side branches on the posterior crest of the upper molars 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).^[7]

Parahippus leonensis was very likely the prey of Amphicyon or bear-dog, and dog-like Temnocyon.

References

External links

• Three-toed horse