Bear Springs, Comanche National Grassland (Cretaceous of the United States)

Where: Colorado (37.3° N, 103.1° W: paleocoordinates 36.9° N, 66.0° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Hartland Shale Member (Greenhorn Limestone Formation), Late/Upper Cenomanian (99.6 - 93.5 Ma)

• ca. 94.6 Ma

•Lower one third of the Hartland Shale Member, roughly 4m above the contact with the underlying Lincoln Limestone Member

• bed-level stratigraphic resolution

Environment/lithology: marine; limestone

• periodic current events and/or depositional hiatuses during which skeletal debris was winnowed and concentrated
• calcarenite

Size classes: macrofossils, mesofossils

Collected in 2006

Primary reference: M. Nagrodski, K. Shimada, and B. A. Schumacher. 2012. Marine vertebrates from the Hartland Shale (Upper Cretaceous: Upper Cenomanian) in southeastern Colorado, USA. Cretaceous Research 37:76-88 [P. Mannion/P. Mannion]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 132505: authorized by Philip Mannion, entered by Philip Mannion on 20.08.2012

Creative Commons license: CC BY (attribution)

Taxonomic list

Bivalvia
 Myalinida - Inoceramidae
Inoceramidae indet. Giebel 1852 clam
 Ostreida - Gryphaeidae
 Vertebrata -
Vertebrata indet. vertebrate
ca. 10,000 bone fragments
Gnathostomata
  -
Chondrichthyes indet. Huxley 1880 cartilaginous fish
1 vertebra
Chondrichthyes
 Hybodontiformes - Ptychodontidae
Ptychodus anonymus Williston 1900 elasmobranch
35 teeth
 Rajiformes - Rhinobatidae
Rhinobatos incertus Cappetta 1973 guitarfish
4 teeth
 Euselachii -
Cretomanta canadensis Case et al. 1990 elasmobranch
1 tooth
 Lamniformes - Anacoracidae
Squalicorax curvatus Williston 1900 crow shark
20 teeth
 Lamniformes - Archaeolamnidae
Archaeolamna kopingensis Davis 1890 mackerel shark
4 teeth
 Lamniformes - Cretoxyrhinidae
Cretoxyrhina mantelli Agassiz 1843 mackerel shark
4 teeth
 Lamniformes - Odontaspididae
Carcharias saskatchewanensis sand shark
24 teeth
Osteichthyes
 Osteichthyes -
Osteichthyes indet. Huxley 1880 bony fish
18 vertebrae
Actinopteri
 Teleostei -
Teleostei "sp. A" Müller 1846
8 teeth
Teleostei "sp. B" Müller 1846
17 teeth
Teleostei "sp. C" Müller 1846
11 teeth
Teleostei "sp. D" Müller 1846
2 teeth
Teleostei indet. Müller 1846
1 jaw bone
 Elopiformes - Elopidae
Elopopsis sp.
22 teeth
 Albuliformes - Albulidae
Albulidae indet. Bleeker 1859 bonefish
1 tooth plate, 4 pieces
 Tselfatiiformes - Plethodidae
Plethodidae indet. Loomis 1900
7 teeth, 6 bones
 Salmoniformes - Enchodontidae
Cimolichthys nepaholica Cope 1872
8 teeth
Enchodus cf. shumardi Leidy 1856
12 teeth
Enchodus cf. gladiolus Cope 1872
3489 teeth, 1 jaw bone
 Crossognathiformes - Pachyrhizodontidae
cf. Pachyrhizodus sp. Agassiz 1850
1 tooth
Pachyrhizodus minimus Stewart 1899
1504 teeth
 Pachycormiformes - Pachycormidae
Protosphyraena sp. Leidy 1857
6 teeth
 Pycnodontiformes - Pycnodontidae
Micropycnodon kansasensis Hibbard and Graffham 1941
3 teeth
 Pycnodontiformes - Nursallidae
Palaeobalistum sp. Blainville 1818
5 teeth
 Amiiformes - Caturidae
Caturidae indet. Owen 1860 bowfin
2 teeth
Osteichthyes
  -
Apateodus sp. Woodward 1901
3 teeth
Reptilia
 Squamata - Dolichosauridae
Coniasaurus crassidens Owen 1850 squamates
18 teeth