Hemicyon Quarry (Miocene of the United States)

Where: San Bernardino County, California (35.1° N, 117.1° W: paleocoordinates 35.8° N, 114.1° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Upper Member (Barstow Formation), Barstovian (16.0 - 13.6 Ma)

Environment/lithology: terrestrial

Size class: macrofossils

Reposited in the AMNH

• AMNH collections only; see for L. A. Mus. no. V491 for later Tedford and Shultz collection

Primary reference: C. Frick. 1937. Horned ruminants of North America. Bulletin of the American Museum of Natural History 69:1-669 [J. Alroy/J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 19364: authorized by John Alroy, entered by John Alroy on 19.05.2000, edited by Jonathan Marcot

Creative Commons license: CC BY (attribution)

Taxonomic list

• Hemicyon Stratum is about "3-30" m below the Hemicyon Tuff and main exposure is in Hemicyon Basin: Woodburne et al. 1990; although not discussed, it seems probable that Hemicyon Quarry is in the Hemicyon Stratum in Hemicyon Basin, and therefore just below the Hemicyon Tuff, which is dated at 14.0 +/- 0.1 Ma by MacFadden et al. 1990 (Ar-Ar)
generalized "Barstow Fauna" records of Woodburne et al. 1990, unless otherwise stated: Megahippus mckennai Merychippus sumani - type is from "Barstow": Merriam 1915d Pliosaccomys sp. "Miomastodon sp." Cynarctus galushai Wang et al. 1999: provenance of specimen unknown, but "preservation suggests Hemicyon Quarry" "Tomarctus" Jakway and Clement 1967: SW 1/4 sec 14 T11N R2W, San Bernardino County, upper Barstow Formation: this is in or near Hemicyon Basin "Tomarctus" Jakway and Clement 1967: UCR V-5201, "Barstow fossil beds" (no further data) Paratomarctus temerarius Wang et al. 1999: "First Division" Aelurodon asthenostylus Wang et al. 1999: "First Division"; "Prospect near Chert Ridge"; "Horizon below Split Ridge" Miolabis cf. fissidens Protolabis cf. barstowensis "Protolabis" cf. inaequidens Aepycamelus alexandrae - type, from "Fossiliferous Tuff member": see Davidson 1923
Mammalia
 Perissodactyla - Rhinocerotidae
Aphelops megalodus6 Cope 1873 rhinoceros
 Perissodactyla - Equidae
Megahippus mckennai2 Tedford and Alf 1962 anchitheriine horse
FAM 21085
 Carnivora - Ursidae
Plithocyon barstowensis3 Frick 1926 bear
 Carnivora - Amphicyonidae
Ischyrocyon sp.4 Matthew and Gidley 1904 bear-dog
 Carnivora - Canidae
Leptocyon leidyi7 Tedford et al. 2009 canine
"Hemicyon stratum"
Microtomarctus conferta8 Matthew 1918 bone-crushing dog
Hemicyon Stratum
Aelurodon asthenostylus8 Wang et al. 1999 bone-crushing dog
Hemicyon Stratum
Paratomarctus temerarius8 Leidy 1858 bone-crushing dog
also Hemicyon Stratum
 Proboscidea - Gomphotheriidae
Gomphotherium sp.5 Burmeister 1837 gomphothere
 Ungulata - Merycoidodontidae
Mediochoerus mohavensis1 Schultz and Falkenbach 1941 oreodont
 Ungulata - Tayassuidae
Dyseohyus fricki9 Stock 1937 peccary
 Ungulata - Antilocapridae
Merycodus joraki1 Frick 1937 pronghorn