Class Mammalia
Order Perissodactyla
Family Equidae

Harris and Porter (1980) tentatively recognized E. scotti from Dry Cave. The metacarpal measurements plot (proximal width against midshaft width: Harris and Porter 1980) close to a topotype of E. scotti. However, measurements taken by Willoughby (1974) of the Rancho La Brea horse (generally treated as E. occidentalis) indicate that the two taxa were about the same size, and it now seems more likely that the specimens identified by Harris and Porter represent E. occidentalis (see the E. occidentalis account for use of the name and further discussion).
Vanderhill (1986) stated that, aside from E. calobatus, there appears to be only one other species of Equus in the valley fill of the Mesilla Basin of southern New Mexico. He identifies this as E. scotti.
How late E. scotti survives into the later Pleistocene is unclear. Lundelius (1972) assigned some horse elements from Blackwater Draw (terminal Pleistocene) to E. scotti; however, Harris and Porter (1980) considered those to represent E. niobrarensis. Winans (1985) considered E. niobrarensis to be a synonym of E. scotti and the chronologic range to be Late Blancan to early Rancholabrean, with the Dry Cave species being E. mexicanus (see discussion in the E. niobrarensis account).
Sites.
Latest Blancan: Caballo (Morgan et al. 2011); La Union (Morgan and Lucas 2003); Santo Domingo (Morgan and Lucas 2003); Virden (Morgan and Lucas 2003).
Pleistocene: Lemitar (Morgan et al. 2009: cf.).
Early Irvingtonian: Hells Canyon (Morgan and Lucas 2005); Adobe Ranch (Morgan and Lucas 2003); Tijeras Arroyo (Morgan and Lucas 2005).
Literature.
Harris and Porter 1980; Lundelius 1972; Morgan and Lucas 2003, 2005; Morgan et al. 2009; Morgan et al. 2011; Vanderhill 1986; Willoughby 1974; Winans 1985.
Last Update: 25 Sep 2011