Hilltop Quarry (Miocene of the United States)

Where: Sioux County, Nebraska (42.4° N, 103.8° W: paleocoordinates 43.1° N, 99.9° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: middle Member (Sheep Creek Formation), Hemingfordian (20.4 - 16.0 Ma)

Environment/lithology: terrestrial

Primary reference: M. F. Skinner, S. M. Skinner, and R. J. Gooris. 1977. Stratigraphy and biostratigraphy of late Cenozoic deposits in central Sioux County, western Nebraska. Bulletin of the American Museum of Natural History 158(5):263-370 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 17952: authorized by John Alroy, entered by John Alroy on 18.02.1993, edited by Jonathan Marcot

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Perissodactyla - Chalicotheriidae
Tylocephalonyx skinneri2 Coombs 1979 chalicothere
 Perissodactyla - Rhinocerotidae
Teleoceras americanum6 Yatkola and Tanner 1979 rhinoceros
Peraceras profectum6 Matthew 1899 rhinoceros
Aphelops megalodus6 Cope 1873 rhinoceros
 Perissodactyla - Equidae
Merychippus primus Osborn 1918 horse
Acritohippus tertius5 Osborn 1918 horse
Supplemental Table S1
Archaeohippus penultimus Matthew 1924 anchitheriine horse
 Carnivora - Amphicyonidae
Cynelos sp.3 Jourdan 1862 bear-dog
 Carnivora - Canidae
Osbornodon fricki8 Wang 1994 canid
Leptocyon leidyi7 Tedford et al. 2009 canine
Protomarctus optatus9 Matthew 1924 bone-crushing dog
 Ungulata - Merycoidodontidae
Brachycrus buwaldi1 Merriam 1919 oreodont
Merychyus relictus Matthew and Cook 1909 oreodont
see Schultz and Falkenbach 1947
 Ungulata - Protoceratidae
cf. Lambdoceras sp. Stirton 1967 protoceratid
"cf. Prosynthetoceras (Lambdoceras) siouxensis": Patton and Taylor 1971; based on discussion species-level referral is impossible
 Ungulata - Leptomerycidae
Pseudoparablastomeryx scotti Frick 1937 ruminant
described by Taylor and Webb 1976
 Ungulata - Palaeomerycidae
Bouromeryx americanus4 Douglass 1899 ruminant