Martin Ranch (Lower) (Pleistocene of the United States)

Also known as Tule Canyon 1

Where: Briscoe County, Texas (34.5° N, 101.3° W: paleocoordinates 34.5° N, 101.1° W)

• coordinate based on political unit

When: lower Member (Tule Formation), Irvingtonian (1.8 - 0.3 Ma)

Environment/lithology: terrestrial

Primary reference: G. E. Schultz. 1986. U Tex Austin Bureau of Economic Geology Guidebook 22 [J. Alroy/J. Alroy]more details

PaleoDB collection 20411: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

• below Cerro Toledo X ash, i.e., below the lower unit of the Cerro Toledo Rhyolite, dated at 1.47 +/- 0.04 (isochron KA) by Izett et al. 1981; this is level 22 of Spell et al. 1996, who redate the unit at 1.474 +/- 0.023 Ma (isochron Ar/Ar on sanidine)
not clear which level following records of Dalquest and Schultz 1992 come from: Cynomys cf. ludovicianus Mammuthus cf. imperator Antilocapridae indet.
Madden 1983 claims that Stegomastodon is present; presumably this is the Upper Martin Ranch specimen
Mammalia
  - Mylodontidae
Mylodontidae indet.2 Ameghino 1889 edentate
 Proboscidea - Elephantidae
Mammuthus sp. Brookes 1828 mammoth
 Perissodactyla - Equidae
Equus sp.1, "Equus simplicidens" = Plesippus simplicidens
Equus sp.1 Linnaeus 1758 horse
"Equus simplicidens" = Plesippus simplicidens Cope 1892 horse
 Artiodactyla - Camelidae
Camelops sp. Leidy 1854 camel