Hancock Quarry (Eocene of the United States)

Also known as Hancock Mammal Quarry; UCMP V-75203; JDNM-13; UO 2473; UWBM #C0082

Where: Wheeler County, Oregon (44.9° N, 120.2° W: paleocoordinates 46.4° N, 105.2° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: uppermost Member (Clarno Formation), Middle Eocene (48.6 - 37.2 Ma)

• The Nut beds have yielded ages between 42 and 44Ma (Manchester 1994; Bestland et al. 1999) placing the locality within the Uintan NALMA. However, several authors have noted Bridgerian fauna from the Clarno vertebrate localities (Stirton 1944; Hanson 1996). Member A of the overlying John Day Formation was dated to ~39 Ma, suggesting the Clarno Formation is also younger than this. Mihlbachler and Samuels 2016 suggest that referring to the Clarno vertebrate localities in terms of NALMA ages is problematic, as Oregan biostratigraphy during the Eocene and Miocene is in need of greater study and the localities share taxa considered characteristic of multiple land mammal ages.

Environment/lithology: terrestrial; conglomerate and sandstone

Size class: macrofossils

Primary reference: C. B. Hanson. 1996. Stratigraphy and vertebrate faunas of the Bridgerian-Duchesnean Clarno Formation, north-central Oregon. In D. R. Prothero and R. J. Emry (eds.), The Terrestrial Eocene-Oligocene Transition in North America 206-239 [J. Alroy/J. Alroy/J. Marcot]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 16842: authorized by John Alroy, entered by John Alroy on 30.04.1994, edited by Patricia Holroyd and Jonathan Marcot

Creative Commons license: CC BY (attribution)

Taxonomic list

• see also Krishtalka et al. 1987; Fremd et al. 1994
122 - 128 m level in a 150 m section of the Clarno according to Retallack et al. OAS abstract; overlies Clarno Nut Bed
just below a welded tuff at the base of the John Day dated at 39.2 Ma (SCLF AA), which is not the same as the basal John Day tuff in the Painted Hills dated at 39.7 Ma; FT zircon and KA dates from the same tuff are slightly younger than the 39.2 Ma date and have considerable errors
NISP 215+
considered Duchesnean by Hanson 1989
"Hesperoceras sp." is a bovid, not a rhinocerotid contra Fremd et al. 1994; I [JA]suspect this is a lapsus or a mistaken manuscript name.
Lucas et al. 2004 reinterpret the radioisotopic data and mammalian composition to arrive at a late Uintan age.
 Testudines - Chelydridae
Chelydridae sp. Swainson 1839 turtle
 Crocodylia - Alligatoridae
 Acreodi - Mesonychidae
Harpagolestes cf. uintensis6 Scott 1888 condylarth
UOMNH F36924
 Creodonta - Hyainailouridae
Hemipsalodon grandis Cope 1885 creodont
mentioned by Gustafson 1986b as from "Clarno"; "H. sp." of Krishtalka et al. 1987 as well as Bryant 1993
 Carnivora - Nimravidae
Nimravidae indet. Cope 1880 false sabre-tooth
see Bryant 1992
 Artiodactyla - Agriochoeridae
Diplobunops kardoula n. sp.2 Emery et al. 2016 agriochoerid
 Artiodactyla - Helohyidae
Achaenodon fremdi n. sp.4 Lucas et al. 2004 even-toed ungulate
 Artiodactyla - Anthracotheriidae
Heptacodon sp. Marsh 1894 anthracothere
 Perissodactyla - Tapiridae
Plesiocolopirus hancocki1 Radinsky 1963 tapir
 Perissodactyla - Rhinocerotidae
Teletaceras radinskyi n. sp. Hanson 1989 rhinoceros
see Hanson 1989: presumably includes "Caenopus sp." of Krishtalka et al. 1987
 Perissodactyla - Amynodontidae
Zaisanamynodon protheroi n. sp.3 Lucas 2006 odd-toed ungulate
NISP not given; said to new, and to be congeneric with Procadurcodon orientalis by Hanson 1989; said to be an "indeterminate amynodontid" by Wall 1998 without further comment
 Perissodactyla - Brontotheriidae
Eubrontotherium clarnoensis n. gen. n. sp.5 Mihlbachler 2007 brontothere
Protitanops curryi4 Stock 1936 brontothere
said to be new; NISP not given
 Perissodactyla - Equidae
Epihippus gracilis Marsh 1871 horse
Haplohippus texanus McGrew 1953 horse
 Placentalia -