Haystack Member (Miocene of the United States)

Where: Wheeler County, Oregon (44.9° N, 120.2° W: paleocoordinates 44.7° N, 114.2° W)

• coordinate based on political unit

When: John Day Formation, Early/Lower Hemingfordian (20.4 - 16.0 Ma)

• overlies "? ATR Tuff" dated at 22.6 Ma (AA)

•said to be 20 Ma or younger based on biochronology, i.e., early Hemingfordian

• member-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size class: macrofossils

Primary reference: T. Fremd. 1994. John Day Basin paleontology field trip guide and road log: Society of Vertebrate Paleontology. John Day Fossil Beds National Monument 94-1 [J. Alroy/J. Alroy/M. Uhen]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 17925: authorized by John Alroy, entered by John Alroy on 30.04.1994, edited by Jonathan Marcot

Creative Commons license: CC BY (attribution)

Taxonomic list

unclassified
  -
Daphaenodon sp.
may include amphicyonid of Fingerut et al. 1993
Mammalia
 Carnivora - Amphicyonidae
Paradaphoenus sp. Wortman and Matthew 1899 bear-dog
presumably includes type of "Daphoenus minimus" from the "Scenic Member" (Hough 1948)
 Carnivora - Canidae
 Perissodactyla - Tapiridae
"Protapirus robustus" = Nexuotapirus robustus
"Protapirus robustus" = Nexuotapirus robustus Sinclair 1901 tapir
 Artiodactyla - Camelidae
Camelidae indet. Gray 1821 camel
 Artiodactyla - Merycoidodontidae
"Pseudodesmatochoerus longiceps" = Merycoides longiceps, Merycochoerus matthewi, "Hypsiops breviceps" = Hypsiops brachymelis, Merychyus arenarum
"Pseudodesmatochoerus longiceps" = Merycoides longiceps Douglass 1907 oreodont
Merycochoerus matthewi Loomis 1924 oreodont
"Hypsiops breviceps" = Hypsiops brachymelis Douglass 1907 oreodont
Merychyus arenarum Cope 1884 oreodont
 Artiodactyla - Entelodontidae
Archaeotherium caninus2 Troxell 1920 even-toed ungulate
UCMP 415: specimen number appears in appendix. Taxonomic assignment from UCMP catalog website
 Rodentia - Heteromyidae
Schizodontomys greeni Rensberger 1973 rodent
 Rodentia - Allomyidae
Rudiomys mcgrewi Rensberger 1983 rodent
"prob. Haystack"
 Rodentia - Mylagaulidae
Mylagaulodon sp. Sinclair 1903 rodent
could be Mesogaulus sensu Korth 1992a
 Rodentia - Entoptychidae
Entoptychus planifrons1 Cope 1878 rodent
Entoptychus individens Rensberger 1971 rodent
 Lagomorpha - Leporidae
Archaeolagus cf. macrocephalus Matthew 1907 rabbit