PBDB Collection

Cook Ranch (Oligocene of the United States)

Also known as MV 7721, MV 7722, MV 7723, MV 7726, MV 7734, MV 7745

Where: Beaverhead County, Montana (45.0° N, 112.8° W)

• Paleocoordinates: 51.6° N, 97.1° W (Wright 2013)

• coordinate based on political unit

• small collection-level geographic resolution

When: upper Member (Sage Creek Formation), Orellan (33.9 - 33.3 Ma)

Environment/lithology: terrestrial

Primary reference: A. R. Tabrum, D. R. Prothero, and D. Garcia. 1996. Magnetostratigraphy and biostratigraphy of the Eocene-Oligocene transition, southwestern Montana. In D. R. Prothero and R. J. Emry (eds.), The Terrestrial Eocene-Oligocene Transition in North America 278-311 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 17090: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Clint Boyd and Jonathan Marcot

Creative Commons license: CC0 (CC0)

Taxonomic list

• originally described by Wood 1937
from two collections 10 m apart according to Wood, which matches discussion of Tabrum et al. 1996
stratigraphic nomenclature supersedes that of Hough 1955

Show authors, comments, and common names

Mammalia
Tribosphenida - Peradectidae	"Nanodelphys hunti" = Nanodelphys huntii "Nanodelphys hunti" = Nanodelphys huntii Cope 1873 marsupial
Tribosphenida - Herpetotheriidae	Herpetotherium fugax, Copedelphys cf. stevensoni Herpetotherium fugax Cope 1873 marsupial includes "H. sp." of Korth 1994; "Didelphidectes pumilis" of Hough 1961; and probably "Peratherium" of Wood 1937 Copedelphys cf. stevensoni Cope 1873 marsupial
Chiroptera - Vespertilionidae	Vespertilionidae indet. Vespertilionidae indet. Gray 1821 vesper bat a bat
Soricomorpha - Proscalopidae	Oligoscalops sp. Oligoscalops sp. Reed 1961 placental said to be new
Soricomorpha - Talpidae	Talpidae indet. Talpidae indet. Fischer de Waldheim 1817 mole two species, said to be new
Soricomorpha - Soricidae	Domnina aff. gradata Domnina aff. gradata Cope 1873 shrew
Soricomorpha - Oligoryctidae	Oligoryctes cf. altitalonidus Oligoryctes cf. altitalonidus Clark 1936 placental
Tribosphenida - Erinaceidae	Ocajila cf. makpiyahe Ocajila cf. makpiyahe Macdonald 1963 hedgehog
Carnivora - Palaeogalidae	Palaeogale sectoria Palaeogale sectoria Gervais 1848 carnivoran
Carnivora - Canidae	Hesperocyon gregarius Hesperocyon gregarius Cope 1873 canid see also Wood 1937
Perissodactyla - Rhinocerotidae	Subhyracodon occidentalis³ Subhyracodon occidentalis³ Leidy 1850 rhinoceros
Perissodactyla - Hyracodontidae	? Hyracodon sp. ? Hyracodon sp. Leidy 1856 odd-toed ungulate see also Wood 1937
Perissodactyla - Equidae	Mesohippus sp. Mesohippus sp. Marsh 1875 anchitheriine horse see also Wood 1937
Artiodactyla - Anthracotheriidae	? Elomeryx sp. ? Elomeryx sp. Marsh 1894 anthracothere
Artiodactyla - Camelidae	Poebrotherium sp. Poebrotherium sp. Leidy 1847 camel
Artiodactyla - Merycoidodontidae	"Merycoidodon cf. culbertsoni" = Merycoidodon culbertsonii, ? Miniochoerus sp. "Merycoidodon cf. culbertsoni" = Merycoidodon culbertsonii Leidy 1848 oreodont ? Miniochoerus sp. Schultz and Falkenbach 1956 oreodont
Artiodactyla - Leptomerycidae	Leptomerycidae indet., Leptomeryx sp., Leptomeryx aff. evansi Leptomerycidae indet. Zittel 1893 ruminant ? Hendryomeryx sp. Leptomeryx sp. Leidy 1853 ruminant said to be new Leptomeryx aff. evansi Leidy 1853 ruminant see also Wood 1937
Rodentia - Cricetidae	Eumys aff. brachyodus, Eumys cf. parvidens, Eumys cf. cricetodontoides¹, Scottimus sp., Willeumys viduus¹, Wilsoneumys focarius n. sp.¹ Eumys aff. brachyodus Wood 1937 rodent Eumys cf. parvidens Wood 1937 rodent Eumys cf. cricetodontoides¹ White 1954 rodent "and/or E. cricetodontoides" Scottimus sp. Wood 1937 rodent Willeumys viduus¹ Korth 1981 rodent Wilsoneumys focarius n. sp.¹ Korth 2019 rodent said to be new
Rodentia - Castoridae	Agnotocastor cf. praetereadens¹ Agnotocastor cf. praetereadens¹ Stirton 1935 beaver
Rodentia - Heliscomyidae	Megaheliscomys mcgrewi¹, Heliscomys gregoryi Megaheliscomys mcgrewi¹ Korth 1989 rodent Heliscomys gregoryi Wood 1933 rodent see also Wood 1933: "H. new species" of Wood 1937
Rodentia - Eomyidae	Metadjidaumo woodi n. sp.¹, Adjidaumo minimus, "Paradjidaumo cf. trilophus" = Adjidaumo trilophus¹ Metadjidaumo woodi n. sp.¹ Korth 2019 rodent said to be new Adjidaumo minimus Matthew 1903 rodent "Paradjidaumo cf. trilophus" = Adjidaumo trilophus¹ Cope 1873 rodent said to be new
Rodentia - Aplodontidae	Disallomys intermedius¹, Brachygaulus nicholsi n. sp.², Brachygaulus nicholsi¹, Ninamys annectens¹, Prosciurinae indet. Disallomys intermedius¹ mountain beaver Brachygaulus nicholsi n. sp.² Korth and Tabrum 2011 mountain beaver see Korth and Tabrum 2011 Brachygaulus nicholsi¹ Korth and Tabrum 2011 mountain beaver said to be new Ninamys annectens¹ Korth 1989 mountain beaver Prosciurinae indet. Wilson 1949 mountain beaver said to be a new genus and species
Rodentia - Cylindrodontidae	? Sespemys sp., Pseudocylindrodon sp. ? Sespemys sp. Wilson 1934 rodent said to be new Pseudocylindrodon sp. Burke 1935 rodent said to be new
Rodentia - Ischyromyidae	Ischyromys sp. Ischyromys sp. Leidy 1856 rodent
Lagomorpha - Leporidae	Megalagus cf. turgidus, Palaeolagus haydeni, "Palaeolagus" cf. burkei Megalagus cf. turgidus Cope 1873 rabbit Palaeolagus haydeni Leidy 1856 rabbit see also Wood 1937 "Palaeolagus" cf. burkei Schlaikjer 1935 rabbit

¹Korth 2019; ²Korth and Tabrum 2011; ³Prothero 2005