Heintzman et al., 2017
For H. francisci
Haringtonhippus is an extinct genus of stilt-legged horse from the Pleistocene of North America first described in 2017. The genus is monospecific, consisting of the species H. francisci, initially described in 1915 by Oliver Perry Hay as Equus francisci. Prior to its formal description, it was sometimes referred to as the New World stilt-legged horse.
Haringtonhippus fossils have only been discovered in North America. Specimens have been found from northern Texas to southern South Dakota and in Alberta, Canada, at sites such as Gypsum Cave and Natural Trap Cave. Evidence shows that the genus evolved in North America. It most likely became extinct around the end of the Pleistocene.
Haringtonhippus is named after Charles Richard Harington. It was originally described as a new Equus species, E. francisci, in 1915. Dalquest (1979) considered Equus tau Owen, 1869, described from teeth in Mexico, a senior synonym of E. francisci, while Equus quinni and E. arrelanoi were synonymized with E. francisci by Winans (1989). The species Equus achates Hay and Cook, 1930 (synonymized with E. tau by Dalquest 1979) was synonymized with E. francisci by Hulbert (1995), who also declared E. tau and E. littoralis nomina dubia.
A 2017 paper by Peter D. Heintzman and colleagues placed Equus francisci outside Equus based on a phylogenetic analysis of DNA sequences, leading to erection of the new genus Haringtonhippus. The genus is phylogenetically closer to Equus than to Hippidion. It is estimated to have diverged from Equus around 4 to 6 million years ago.
- Hay, Oliver P. (1915). "Contributions to the Knowledge of the Mammals of the Pleistocene of North America". Proceedings of the United States National Museum. 48 (2086): 535–549. doi:10.5479/si.00963801.48-2086.515.
- †Equus francisci Hay 1915 (horse) at fossilworks.org (retrieved 29 November 2017)
- Heintzman, P.D.; Zazula, G.D.; MacPhee, R.D.E; Scott, E.; Cahill, J.A.; McHorse, B.K.; Kapp, J.D.; Stiller, M.; Wooller, M.J.; Orlando, L.; Southon, J.; Froese, D.G.; Shapiro, B. (2017). "A new genus of horse from Pleistocene North America". eLife. 6. doi:10.7554/eLife.29944.
- Weinstock, Jaco; Willerslev, Eske; Sher, Andrei; Tong, Wenfei; Ho, Simon Y.W; Rubenstein, Dan; Storer, John; et al. (2005). "Evolution, Systematics, and Phylogeography of Pleistocene Horses in the New World: A Molecular Perspective". PLoS Biology. 3 (8): e241. doi:10.1371/journal.pbio.0030241.
- Dalquest, Walter W. (1979). "The Little Horses (Genus Equus) of the Pleistocene of North America". The American Midland Naturalist. 101 (1): 241–244. doi:10.2307/2424920. JSTOR 2424920.
- Winans, M. C. 1989. A quantitative study of the North American fossil species of the genus Equus. Pp. 262-297, in The evolution of perissodactyls (D. R. Prothero & R. M. Schoch, eds.), Oxford Monographs Geol. Geophysics, no. 15, 537 pp.
- Hulbert, R. C. 1995. Equus from Leisey Shell Pit 1A and other Irvingtonian localities from Florida. Bulletin of the Florida Museum of Natural History 37:553—602.