Belmont Grade: Harrisonian, Nebraska

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Mammalia - Talpidae
? Scalopoides sp. Wilson 1960
Mammalia - Proscalopidae
Proscalops secundus Matthew 1909
Mammalia - Erinaceidae
Parvericius sp. Koerner 1940
Mammalia - Rodentia - Sciuridae
Tamias sp. Illinger 1811
    = Tamiini indet.
Alroy 2007
synonym of Marmotini
Mammalia - Rodentia - Castoridae
Palaeocastor sp. Leidy 1869
Mammalia - Rodentia - Heteromyidae
cf. Mookomys sp. Wood 1931
Dikkomys matthewi Wood 1936
Proheteromys sp. Wood 1932
Mammalia - Rodentia - Cricetidae
Leidymys sp. Wood 1936
Mammalia - Rodentia - Zapodidae
Schaubeumys sp. Wood 1935
Mammalia - Rodentia - Mylagaulidae
Promylagaulus riggsi McGrew 1941
Mammalia - Rodentia - Entoptychidae
Entoptychus grandiplanus Korth 1992
Mammalia - Rodentia - Florentiamyidae
Florentiamys sp. Wood 1936
Hitonkala sp. Macdonald 1963
Mammalia - Lagomorpha - Ochotonidae
Gripholagomys lavocati Green 1972
Mammalia - Lagomorpha - Leporidae
? Archaeolagus sp. Dice 1917
Mammalia
Herpetotherium youngi (McGrew 1937)
see common names

Geography
Country:United States State/province:Nebraska County:Dawes
Coordinates: 42.6° North, 103.3° West (view map)
Paleocoordinates:43.4° North, 98.3° West
Basis of coordinate:based on nearby landmark
Altitude:4730 feet
Geographic resolution:small collection
Time
Key time interval:Harrisonian
Age range of interval:24.80000 - 20.43000 m.y. ago
Stratigraphy
Geological group:Arikaree Formation:Coffee Mill Butte Beds
Stratigraphic resolution:bed
Stratigraphy comments: "late late Arikareean" (= Harrisonian)
Lithology and environment
Primary lithology:very fine,volcaniclastic,shelly/skeletal,brown sandstone
Lithology description: "lens of fragmentary bone/tooth 'puddingstone'... absence of fluvial bedding... 10 m interval... is characterized by 1.8 m beds of brown, well sorted, very fine-grained, eolian volcaniclastic sandstone bounded by calcareous ledges... A single helical burrow (Daemonelix) [was] discovered near the base of this unit"
Environment:eolian indet.
Taphonomy
Modes of preservation:body
Size of fossils:mesofossils
Articulated whole bodies:none
Associated major elements:none
Disassociated major elements:some
Disassociated minor elements:many
Collection methods and comments
Collection methods:selective quarrying,field collection
Collection size:218 specimens
Reason for describing collection:biostratigraphic analysis
Museum repositories:UNSM
Collection method comments: "in situ concentration of vertebrate debris... Less than 2.3 kg of concentrate, composed of roughly 25 percent vertebrate tooth and bone fragments... microfauna. Reptile elements including dentaries were abundant, however, no fish, amphibian, or bird remains were recovered. Small mammals are represented by 11 jaw framgents with one or more teeth and 207 isolated cheek teeth."
Taxonomic list comments:fauna apart from mammals not discussed
Metadata
Also known as:UNSM Dw-123
Database number:69806
Authorizer:J. Alroy Enterer:J. Alroy
Modifier:J. Alroy Research group:vertebrate
Created:2007-03-07 21:18:18 Last modified:2007-03-07 23:29:13
Access level:the public Released:2007-03-07 21:18:18
Creative Commons license:CC BY
Reference information

Primary reference:

19303. B. E. Bailey. 2004. Biostratigraphy and biochronology of early Arikareean through late Hemingfordian small mammal faunas from the Nebraska Panhandle and adjacent areas. Paludicola 4(3):81-113 [J. Alroy/J. Alroy]

Secondary references:

19636 J. Alroy. 2007. Synonymies and reidentifications of North American fossil vertebrates and so forth. [J. Alroy/J. Alroy]