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 46.6° N, 104.7° W)

• 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: CC BY (attribution)

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
Chiroptera - Vespertilionidae	Vespertilionidae indet. Vespertilionidae indet. Gray 1821 vesper bat a bat
Carnivora - Canidae	Hesperocyon gregarius Hesperocyon gregarius Cope 1873 canid see also Wood 1937
Carnivora - Palaeogalidae	Palaeogale sectoria Palaeogale sectoria Gervais 1848 carnivoran
Perissodactyla - Equidae	Mesohippus sp. Mesohippus sp. Marsh 1875 anchitheriine horse 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
Artiodactyla - Anthracotheriidae	? Elomeryx sp. ? Elomeryx sp. Marsh 1894 anthracothere
Artiodactyla - Merycoidodontidae	? Miniochoerus sp., "Merycoidodon cf. culbertsoni" = Merycoidodon culbertsonii ? Miniochoerus sp. Schultz and Falkenbach 1956 oreodont "Merycoidodon cf. culbertsoni" = Merycoidodon culbertsonii Leidy 1848 oreodont
Artiodactyla - Camelidae	Poebrotherium sp. Poebrotherium sp. Leidy 1847 camel
Artiodactyla - Leptomerycidae	Leptomeryx sp., Leptomeryx aff. evansi, ? Hendryomeryx sp. Leptomeryx sp. Leidy 1853 ruminant said to be new Leptomeryx aff. evansi Leidy 1853 ruminant see also Wood 1937 ? Hendryomeryx sp. Black 1978 ruminant
Theriamorpha - Talpidae	Talpidae indet. Talpidae indet. Fischer de Waldheim 1817 mole two species, said to be new
Theriamorpha - Proscalopidae	Oligoscalops sp. Oligoscalops sp. Reed 1961 placental said to be new
Theriamorpha - Soricidae	Domnina aff. gradata Domnina aff. gradata Cope 1873 shrew
Theriamorpha - Oligoryctidae	Oligoryctes cf. altitalonidus Oligoryctes cf. altitalonidus Clark 1936 placental
Theriamorpha - Erinaceidae	Ocajila cf. makpiyahe Ocajila cf. makpiyahe Macdonald 1963 hedgehog
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
Rodentia - Cricetidae	Scottimus sp., Eumys cf. parvidens, Eumys aff. brachyodus, Eumys cf. cricetodontoides¹, Willeumys viduus¹, Wilsoneumys focarius n. sp.¹ Scottimus sp. Wood 1937 mouse Eumys cf. parvidens Wood 1937 mouse Eumys aff. brachyodus Wood 1937 mouse Eumys cf. cricetodontoides¹ White 1954 mouse "and/or E. cricetodontoides" Willeumys viduus¹ Korth 1981 mouse Wilsoneumys focarius n. sp.¹ Korth 2019 mouse said to be new
Rodentia - Cylindrodontidae	Pseudocylindrodon sp., ? Sespemys sp. Pseudocylindrodon sp. Burke 1935 rodent said to be new ? Sespemys sp. Wilson 1934 rodent said to be new
Rodentia - Aplodontidae	Ninamys annectens¹, Disallomys intermedius¹, Brachygaulus nicholsi n. sp.², Brachygaulus nicholsi¹, Prosciurinae indet. Ninamys annectens¹ Korth 1989 mountain beaver 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 Prosciurinae indet. Wilson 1949 mountain beaver said to be a new genus and species
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	"Paradjidaumo cf. trilophus" = Adjidaumo trilophus¹, Adjidaumo minimus, Metadjidaumo woodi n. sp.¹ "Paradjidaumo cf. trilophus" = Adjidaumo trilophus¹ Cope 1873 rodent said to be new Adjidaumo minimus Matthew 1903 rodent Metadjidaumo woodi n. sp.¹ Korth 2019 rodent said to be new
Rodentia - Ischyromyidae	Ischyromys sp. Ischyromys sp. Leidy 1856 rodent
Theriamorpha - Peradectidae	"Nanodelphys hunti" = Nanodelphys huntii "Nanodelphys hunti" = Nanodelphys huntii Cope 1873 marsupial
Theriamorpha - Herpetotheriidae	Copedelphys cf. stevensoni, Herpetotherium fugax Copedelphys cf. stevensoni Cope 1873 marsupial Herpetotherium fugax Cope 1873 marsupial includes "H. sp." of Korth 1994; "Didelphidectes pumilis" of Hough 1961; and probably "Peratherium" of Wood 1937

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