State Line Quarry (Eocene of the United States)

Also known as Thomas Canyon

Where: Uinta County, Wyoming (41.3° N, 111.0° W: paleocoordinates 45.4° N, 97.6° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Bulldog Hollow Member (Fowkes Formation), Bridgerian (50.3 - 46.2 Ma)

• all fossils are from a single quarry within a member

• group of beds-level stratigraphic resolution

Environment/lithology: terrestrial; tuffaceous mudstone and sandstone

• "tuffaceous mudstone, sandstone, and siliceous limestone" (Nelson 1973) or "tuffaceous mudstone and sandstone" (Nelson 1974, 1977)

Size classes: macrofossils, mesofossils

Collection methods: quarrying,

Primary reference: M. E. Nelson. 1973. Age and stratigraphic relationships of the Fowkes Formation, Eocene, of southwestern Wyoming and northeastern Utah. Contributions to Geology, University of Wyoming 12(1):27-31 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 16418: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

• close to the Utah state line and well west of the Green River Basin

•date of 47.9 (49.1 corrected) +/- 1.9 Ma (K-Ar on biotite) on a sample immediately above the quarry; date of 47.7 Ma reported earlier is from a site 48 km to the north

Reptilia
 Testudines - Kinosternoidea
Xenochelys bridgerensis3 Hutchison 1991 mud turtle
UCMP loc V74135=State Line Quarry
 Testudines - Pangeoemydidae
Bridgeremys pusilla4 Hay 1908 turtle
Mammalia
 Primates - Microsyopidae
Uintasorex parvulus Matthew 1909 primate
 Primates - Omomyidae
Omomys carteri Leidy 1869 tarsier
Hemiacodon gracilis Marsh 1872 tarsier
 Primates - Notharctidae
Notharctus cf. robustior5 Leidy 1872 primate
 Rodentia - Sciuravidae
Sciuravidae indet. Miller and Gidley 1918 rodent
Pauromys sp. Troxell 1923 rodent
 Rodentia - Muridae
Mysops parvus Marsh 1872 mouse
 Rodentia - Ischyromyidae
? Tillomys sp. Marsh 1872 rodent
Microparamys minutus Wilson 1937 rodent
? Paramys aff. excavatus Loomis 1907 rodent
Thisbemys corrugatus Wood 1959 rodent
Leptotomus parvus2 Wood 1959 rodent
 Rodentia - Paramyidae
Paramyidae indet. Miller and Gidley 1918 rodent
two forms, close to Leptotomus
 Perissodactyla - Hyrachyidae
Hyrachyus modestus Leidy 1870 odd-toed ungulate
 Perissodactyla - Equidae
Orohippus sp. Marsh 1872 horse
 Tribosphenida - Nyctitheriidae
Nyctitherium serotinum Marsh 1872 placental
 Tribosphenida -
Talpavus cf. nitidus Marsh 1872 placental
 Carnivora - Miacidae
Miacidae indet. Cope 1880 carnivoran
Miacis parvivorus Cope 1872 carnivoran
 Macroscelidea - Amphilemuridae
Scenopagus priscus Marsh 1872 elephant shrew
 Ungulata - Hyopsodontidae
Hyopsodus lepidus Matthew 1909 condylarth
 Ungulata - Uintatheriidae
? Uintatherium sp. Leidy 1872 uintathere
 Insectivora -
Insectivora indet. Bowdich 1821 insectivoran
three forms
 Insectivora - Apatemyidae
Apatemys bellus Marsh 1872 insectivoran
 Theriiformes - Herpetotheriidae
"Herpetotheriinae indet." = Herpetotheriidae1
"Herpetotheriinae indet." = Herpetotheriidae1 Trouessart 1879 marsupial