Mammalia - Perissodactyla - Equidae
Alternative spelling: Equus (Protohippus)
Full reference: J. Leidy. 1858. Notice of Remains of Extinct Vertebrata, from the Valley of the Niobrara River, Collected during the Exploring Expedition of 1857, in Nebraska, under the Command of Lieut. G. K. Warren, U. S. Top. Eng., by Dr. F. V. Hayden, Geologist to the Expedition. Proceedings of the Academy of Natural Sciences of Philadelphia 10:15-89
Parent taxon: Merychippus according to R. A. Stirton 1940
See also Carroll 1988, Cope 1881, Dorr 1956, Gidley 1907, Hay 1902, Hulbert and Whitmore 2006, Hulbert 1988, Kelly 1995, Leidy 1858, Leidy 1869, Leidy 1873, MacFadden 1998, MacFadden and Dobie 1998, May 2019, McGrew and Meade 1938, Olson and McGrew 1941, Prado and Alberdi 1996, Prothero and Schoch 1989, Quinn 1955, Scott 1913 and Shotwell 1961
Sister taxa: Merychippus (Merychippus), Merychippus brevidontus, Merychippus calamarius, Merychippus californicus, Merychippus coloradense, Merychippus eohipparion, Merychippus eoplacidus, Merychippus gunteri, Merychippus insignis, Merychippus isonesus secundus, Merychippus labrosus, Merychippus missouriensis, Merychippus patruus, Merychippus primus, Merychippus proparvulus, Merychippus quartus, Merychippus quintus, Merychippus relictus, Merychippus republicanus, Merychippus sejunctus, Merychippus seversus, Merychippus stevensi
Subtaxa: Merychippus (Protohippus) secundus
Type: Protohippus perditus
Distribution: there are no occurrences of Merychippus (Protohippus) in the database