Brecht Ranch (Eocene of the United States)

Also known as TNAS

Where: Dawes County, Nebraska (42.8° N, 103.1° W: paleocoordinates 44.1° N, 94.3° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Chadron Formation, Chadronian (37.2 - 33.9 Ma)

Environment/lithology: terrestrial

Primary reference: E. P. Gustafson. 1986. Preliminary biostratigraphy of the White River Group (Oligocene, Chadron and Brule formations) in the vicinity of Chadron, Nebraska. Transactions of the Nebraska Academy of Sciences 14:7-20 [J. Alroy/J. Alroy/M. Uhen]more details

PaleoDB collection 16918: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

• includes CSC-55 Bartlett West #1 CSC-92 Rook Ranch lower levels (= UNSM Dw-104: Hunt 1998b) CSC-99 White's south end CSC-26 Hawthorne A CSC-27 Hawthorne B CSC-5 (in part) Schommer Ranch lower level
apparently in the Trunk Butter Member sensu LaGarry and LaGarry 1999
Brecht Ranch, level indeterminate: Paratylopus labiatus Prothero 1996d: presumably Orellan; also at "Morris Ranch"
possibly relevant: Parictis sp. Hunt 1998a: "Chadron Formation, sect. 2, T32N, R52W, Dawes County"
NISP 67, excluding brontotheres
Mammalia
 Creodonta - Hyaenodontidae
Hyaenodon crucians Leidy 1853 creodont
 Carnivora - Amphicyonidae
"Daphoenocyon dodgei" = Brachyrhynchocyon dodgei Scott 1898 bear-dog
also present at "Rook Ranch (Dw-104)" and Bartlett Ranch West #1: Hunt 1998b
Daphoenictis tedfordi Hunt 1974 bear-dog
mentioned also by Hunt 1974, Hunt 1996
 Carnivora - Canidae
Hesperocyon gregarius Cope 1873 canid
specimen from KU-NE-083 "Chadronian" of Walter Brecht Ranch listed by Wang 1994
 Carnivora - Nimravidae
Dinictis felina Leidy 1854 false sabre-tooth
 Perissodactyla - Equidae
Mesohippus bairdi Leidy 1850 anchitheriine horse
also "M. proteulophus"
 Perissodactyla - Brontotheriidae
Brontotheriidae indet. Marsh 1873 brontothere
 Perissodactyla - Hyracodontidae
Hyracodon nebraskensis Leidy 1850 odd-toed ungulate
probably OK because Ostrander also recognizes H. priscidens
 Artiodactyla - Entelodontidae
Archaeotherium mortoni Leidy 1850 even-toed ungulate
 Artiodactyla - Merycoidodontidae
Miniochoerus gracilis Leidy 1851 oreodont
Miniochoerus forsythae2 Schultz and Falkenbach 1968 oreodont
"Merycoidodon culbertsoni" = Merycoidodon culbertsonii Leidy 1848 oreodont
includes "M. culbertsonii browni" and "M. culbertsoni osborni" of Schultz and Falkenbach 1968 from UNSM Dw-104, Chadron C
 Artiodactyla - Camelidae
Poebrotherium eximium1 Hay 1902 camel
"2.5 miles north of Chadron... Brecht Ranch, Morris Ranch - late Chadronian"
 Artiodactyla - Protoceratidae
Pseudoprotoceras longinaris Cook 1934 protoceratid
 Artiodactyla - Agriochoeridae
Agriochoerus antiquus Leidy 1850 agriochoerid
 Artiodactyla - Hypertragulidae
Hypertragulus calcaratus Cope 1873 ruminant
 Artiodactyla - Leptomerycidae
Leptomeryx sp. Leidy 1853 ruminant
large
Leptomeryx evansi Leidy 1853 ruminant
 Lagomorpha - Leporidae
Palaeolagus haydeni Leidy 1856 rabbit