Class Mammalia
Order Perissodactyla
Family Equidae
Synonyms. Equus caballus caballus, E. caballus laurentius, E. excelsus, E. laurentius, E. midlandensis, E. scotti of the Southwest.
Horse taxonomy has been plagued by an overload of described forms. The taxon recognized by Harris and Porter (1980) as E. niobrarensis appears to have been recognized under a number of synonyms (for reasoning behind the synonymy, see Harris and Porter 1980; Winans 1985). Equus laurentius, especially, has been used relatively recently in the literature. However, Scott et al. (2003), in a poster presentation, and later in a full, evidenced publication (Scott et al. 2010), showed that E. laurentius is based on modern domestic horse material only a few hundred years old. Various other authors, including Winans (1985), also have suggested this (interestingly, Winans in her 1989 work nevertheless applied the name to one of her species groups). Winans (1985) considered E. niobrarensis to be a synonym of E. scotti and, in her 1989 paper, assigned the Dry Cave horses to E. mexicanus, to which she also assigned the Rancho La Brea horses generally labeled as E. occidentalis. See the latter account for the problems with this assignment. Also, Scott et al. (2010) note a problem with the name, E. mexicanus.
Fig. 1. Comparison of first phalanges of E. niobrarensis (top) and Equus conversidens. Left images are of presumed anterior first phalanges and right images of posterior first phalanges.
This is a medium-size horse that commonly occurs together with E. conversidens in Southwestern fossil faunas. Harris and Porter (1980) give a number of measurements separating E. niobrarensis from E. conversidens.
Sites.
Pleistocene: Agua Negra (Morgan and Lucas 2005); Gobernador (Morgan and Lucas 2005); Jemez Springs (Morgan and Lucas 2005); Nash Draw (Harris 1993c: cf.); Perico Creek (Morgan and Lucas 2005); Plaza Larga Creek (Morgan and Lucas 2003); Steins (Morgan and Lucas 2005); Tome (Morgan and Lucas 2005); West Fork Kutz Canyon (Morgan and Lucas 2005).
Late Irvingtonian or Early Rancholabrean (?): Taiban Creek (Morgan and Lucas 2005).
Early Rancholabrean: Albuquerque Gravel Pits (Morgan and Lucas 2005).
Rancholabrean: Alkali Spring (Morgan and Lucas 2005); Casados Ranch (Morgan and Lucas 2005); Jal (Morgan and Lucas 2005); Tramperos Creek (Morgan and Lucas 2005); Twenty Five Mile Stream (Morgan and Lucas 2005).
Mid Wisconsin: Pendejo Cave (Harris 2003); U-Bar Cave (Harris 1987: cf.).
Mid/Late Wisconsin: Dark Canyon Cave (Harris and Porter 1980); Pit N&W Animal Fair (Harris 1993c).
Late Wisconsin: Anderson Basin et al. (Morgan and Lucas 2005); Animal Fair (Harris and Porter 1980); Balcony Room (Harris 1993c); Big Manhole Cave (Harris 1993c); Bison Chamber (Harris and Porter 1980); Blackwater Draw Fauna (Slaughter 1975); Camel Room (Harris and Porter 1980); Charlies Parlor (Harris and Porter 1980); Cueva Quebrada (Lundelius 1984: E. cf. scotti); Harris' Pocket (Harris 1989); Human Corridor (Harris and Porter 1980: ?); Lake Estancia (Morgan and Lucas 2005); Placitas (Hibben 1941); Salt Creek (UTEP: cf.); Sandia Cave, Sandia Level (Hibben 1941); Sandia Gravel Pit (Morgan and Lucas 2005); Stalag 17 (Harris and Porter 1980); TT II (Harris and Porter 1980); U-Bar Cave 14-15 (Harris 1989: cf.).
Late Wisconsin/Holocene: Isleta Cave No. 1 (Harris 1993c: cf.); Isleta Cave No. 2 (Harris 1993c: cf.); Burnet Cave (Schultz and Howard 1935); Beyond Bison Chamber (Harris 1993c: cf.).
Literature.
Harris 1987, 1989, 1993c, 2003; Harris and Porter 1980; Hibben 1941; Lundelius 1984; Morgan and Lucas 2003, 2005; Schultz and Howard 1935; Scott et al. 2003; Scott et al. 2010; Slaughter 1975; Winans 1985, 1989.
Last Update: 20 May 2013