Protorohippus
________________________
[1] https://www.nps.gov/fobu/learn/nature/fossil-mammals.htm
[2] http://touchstonegalleryandmineralandfossil.blogspot.com/2012/02/oldest-most-complete-horse-fossil-in.html
[3] ibid.
[4] https://en.wikipedia.org/wiki/Protorohippus
[5] http://touchstonegalleryandmineralandfossil.blogspot.com/2012/02/oldest-most-complete-horse-fossil-in.html
[6] wikipedia, Ibid.
[7] Wikimedia Commons, public domain photo, background has been modified from original and shadows removed
[8] Public domain photo
[9] F. John, artist,Tiere der Unwelt, Series 2 (Germany, 1906?)
 
Skeleton
Protorohippus venticolum
Skeleton Cast
Protorohippus venticolum
Most complete skeleton ever found for this
animal with only part of tail missing
Fd. Green River Formation, Wyoming, USA
By Harpers [6]
NPS [7]
Synonyms [6]:
Hyracotherium venticolum Cope, 1881
Hyracotherium vasacciense venticolum Kitts, 1956
Eohippus venticolum Granger, 1908
Restoration by F. John [9]
Copyright 2018 All rights reserved.

 

Size

2 feet long, 1.67 feet tall [1], 1 foot tall at shoulders [2]

Eye sockets

Incomplete bony rim, about 0.59 of skull length from front of skull to center of socket

Type of teeth

Low crowned

Toes

Four toes on foreleg and 3 toes on hindleg [3]

Hooves/pads

Pads

Locations found

North America [4]

Other

Almost complete fossil skeleton of Protorohippus venticolum, except portion of tail, fd. Green River Formation, Wyoming, USA [5]

Back arched upward

Nineteen rib pairs per first skeleton below

Spinous processes unusually long on four cervical vertebraes per first skeleton below

Anchippus
Anchitherium
Equus 1 (Recent)
Equus 2 (Recent)
Equus 1 (Fossils)
Equus 2 (Fossils)
Hipparion
Hippidion
Hypohippus
Kalobatippus
Merychippus
Mesohippus
Miohippus
Nannippus
Neohipparion
Orohippus
Parahippus
Pliohippus
Protohippus
Protorohippus
Unidentified
Hyracotherum (Eohippus)
Horse Evolution?