Geologic formation of the Upper Cretaceous from Pembina Valley in Canada to New Mexico, USA
Baculites from the Pierre Shale showing sutures and remnant aragonite ; western South Dakota, Late Cretaceous.
The Pierre Shale is a geologic formation or series in the Upper Cretaceous which occurs east of the Rocky Mountains in the Great Plains , from Pembina Valley in Canada [ 2] to New Mexico .
The Pierre Shale was described by Meek and Hayden in 1862 in the Proceedings of the Academy of Sciences (Philadelphia). They described it as a dark-gray shale , fossiliferous, with veins and seams of gypsum , and concretions of iron oxide . The Pierre Shale is about 3,138 feet (956m) thick at the type locality. It overlies the Niobrara division and underlies the Fox Hills beds.[ 1] It was named for an occurrence near Fort Pierre on the Missouri River in South Dakota .[ 3]
The Pierre Shale is of marine origin and was deposited in the Western Interior Seaway . It is correlative with other marine shales that occur farther west, such as the Bearpaw Shale , Mancos Shale and the Lewis Shale .[ 4] It correlates with the Lea Park Formation in central Alberta .[ 5] The Pierre is overlain by marginal marine deposits of the Fox Hills Formation .
Most of the formation was deposited in the Campanian Age of the late Cretaceous . However, the discovery of fossils of Baculites baculus in the uppermost beds of the Pierre Shale in the Raton, New Mexico area show that deposition continued here into the early Maastrichtian .[ 6]
Mineral resources
The Pierre Shale is the host formation for commercial petroleum deposits in the Florence and Canon City fields in Fremont County, Colorado , and the Boulder Oil Field in Boulder County, Colorado . More recently, natural gas has been extracted in the Raton Basin in southern Colorado . The shale formation is usually too impermeable for hydrocarbon extraction, but produces in areas where it is naturally fractured or fractured by artificial means .
Paleofauna
Color key
Notes Uncertain or tentative taxa are in small text ; crossed out taxa are discredited.
Reptiles
Dinosaurs
Birds reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Brodavis
B. varneri
South Dakota
Sharon Springs Member.[ 7]
A hesperornithiform .
B. sp.
Manitoba
Pembina Member.[ 7]
A hesperornithiform .
Hesperornis
H. bairdi
South Dakota
Sharon Springs Member.[ 7]
A hesperornithid .
H. chowi
Manitoba & South Dakota
Pembina, Millwood, & Sharon Springs Members.[ 7]
A hesperornithid .
H. lumgairi
Manitoba
Pembina Member.[ 7]
A hesperornithid .
H. macdonaldi
Manitoba & South Dakota.
Gammon, Pembina, Millwood(?), & Sharon Springs Members.[ 7]
A hesperornithid .
H. mengeli
Manitoba & South Dakota.
Pembina & Sharon Springs Members.[ 7]
A hesperornithid .
H. regalis
Manitoba, South Dakota, & Kansas
Gammon, Pembina, & Sharon Springs Members.[ 7] [ 8]
A hesperornithid .
H. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
Probably referrable to H. regalis , but indistinguishable from H. crassipes .[ 8]
Hesperornithidae
Gen. et. sp. indeterminate
Manitoba.[ 8]
Pembina Member.[ 8]
Multiple isolated synascra .[ 8]
A hesperornithid .
Hesperornithiformes
Fam., gen. et sp. indet.
Manitoba.[ 8]
Pembina Member.[ 8]
Multiple vertebrae, phalanges, tibiotarsal fragments and a fibula .[ 8]
Ichthyornis
I. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
"MDM B77.03.07 (vertebral centrum), B80.05.14 (femur)".[ 8]
An ichthyornithe .
Ornithischians reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Claosaurus
C. affinis
South Dakota.[ 9]
"Pedal phalanx (lost)."[ 10]
Currently considered dubious .
Mosasaurs
Mosasaurs reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Clidastes
C. propython
Manitoba.[ 8]
Pembina Member.[ 8]
MDM M74.10.06 (skull, mandible, vertebral column).[ 8]
A mosasaurine also known from the Mooreville Chalk .
Western Kansas.[ 11]
Vertebrae associated with 'Plesiosaurus' gulo currently lost.[ 12]
Likely represents the stomach contents of 'Plesiosaurus' gulo .[ 12]
Globidens
G. dakotensis
South Dakota.[ 13]
Sharon Springs Member.[ 13]
FMNH PR 846.[ 13]
A globidensin .
G. schurmanni
At the Big Bend of the Missouri River , Buffalo County, South Dakota .[ 14]
Uppermost DeGrey Formation.[ 14]
"SDSM 74764, partial anterior skeleton, including cranium , jaws, cervical and trunk vertebrae partially articulated, pectoral girdles, partial anterior paddle, isolated humerus and ulna , and isolated caudal vertebrae ".[ 14]
G. sp.
Northwestern Logan County, Kansas .[ 13]
Upper level of the Sharon Springs Member.[ 13]
A nearly complete right dentary (FHSM VP–13828).[ 13]
A globidensin .
Hainosaurus
H. pembinensis
Near Morden, Manitoba .[ 15]
Pembina Member.[ 8] [ 15]
Reassigned to the genus Tylosaurus .
Jormungandr
J. walhallaensis
Cavalier County, North Dakota .[ 16]
Pembina Member.[ 16]
Partial skull & skeleton.[ 16]
A mosasaurine .
Latoplatecarpus
L. nichollsae
"19 km northwest of Morden, Manitoba ".[ 17]
Pembina Member.[ 17]
A skeleton (CMN 52261).[ 17]
A plioplatecarpine .
Mosasauridae
Subfam., gen. et. sp. indeterminate
Manitoba.[ 8]
Pembina Member.[ 8]
Fragmentary specimens consisting "mostly of vertebral scraps, ribs and flipper elements".[ 8]
Platecarpus
P. coryphaeus
Pembina Member.[ 8]
Now deemed synonymous with P. tympaniticus .
P. ictericus
Pembina Member.[ 8]
Now deemed synonymous with P. tympaniticus .
P. somenensis
Pembina Member.[ 8]
Found to nest within Latoplatecarpus nichollsae .
P. tympaniticus
Pembina Member.[ 8]
Abundant specimens.[ 8]
A pliopatecarpine and the most abundant mosasaur of the Pierre Shale.
P. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
"Isolated skull elements, humeri and pectoral girdles".[ 8]
Probably referrable to P. tympaniticus based on size, but size alone is deemed insufficient for species identification.[ 8]
Plioplatecarpinae
Gen. et. sp. indeterminate
Manitoba.[ 8]
Pembina Member.[ 8]
Poorly preserved and unprepared remains.[ 8]
Plioplatecarpus
P. nichollsae
"19 km northwest of Morden, Manitoba ".[ 17]
Pembina Member.[ 17]
A skeleton (CMN 52261).[ 17]
Reassigned to the genus Latoplatecarpus .[ 18]
Prognathodon
P. overtoni
South Dakota.[ 19]
Virgin Creek Member.[ 19]
KUVP 950 (the holotype for the species) and SDSM 3339.[ 19]
A mosasaurine also found in the Bearpaw Shale .
Tylosaurinae
Gen. et. sp. indet.
Manitoba.[ 8]
Pembina Member.[ 8]
Isolated limb and girdle elements (MDM M74.28.05, M75.20.06, M82.13.17, M84.09.18).[ 8]
Tylosaurus
T. pembinensis
Near Morden, Manitoba .[ 15]
Pembina Member.[ 15]
A tylosaurine .
T. proriger
Manitoba .[ 8]
Pembina Member.[ 8]
MDM M77.17.07 quadrate, FMNH PR 591 quadrate, pubis, vertebrae.[ 8]
A tylosaurine .
Plesiosaurs
Plesiosaurs reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Alzadasaurus
A. pembertonii
South Dakota.[ 8]
Sharon Springs Member.[ 8]
Complete specimen (SDSM 451).[ 8]
Synonymized with Styxosaurus snowii .
cf. A. pembertonii
Manitoba.[ 8]
Pembina Member.[ 8]
A specimen consisting of two femora, one humerus, two epipodials, fragments of the pelvic girdle and 14 vertebrae (MDM P83.02. 18).[ 8]
Synonymized with Styxosaurus snowii .
Elasmosauridae
Gen. et. sp. indeterminate
Manitoba.[ 8]
Pembina Member.[ 8]
Remains undiagnostic at the generic level.[ 8]
Logan County, Kansas .[ 20]
Upper Sharon Springs Member.[ 20]
KUVP 129744, a specimen associated with 47 gastroliths.[ 20]
An elasmosaurid too fragmentary to identify below the family level.[ 20]
Elasmosaurus
E. platyurus
Kansas.[ 21] [ 22]
Sharon Springs member.[ 21] [ 22]
Multiple specimens, including the holotype.[ 21]
An elasmosaurid .
?E. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
"An incomplete specimen (TMP P84.162.4), consisting of pelvic girdle, distal end of a propodial, an epipodial and 21 vertebrae".[ 8]
Martinectes
M. bonneri
Wyoming & South Dakota.[ 23] [ 24]
Sharon Springs Member and Pembina Member.[ 8]
2 specimens: an adult (UNSM 50133) and a juvenile (UNSM 55810),[ 23] [ 24] and several others.[ 8]
A polycotylid .
Plesiosauria
Fam., gen. et. sp. indeterminate
Pembina Member.[ 8]
"Specimens consisting mostly of ribs, caudal vertebrae, broken girdle plates and phalanges".[ 8]
"Further identification is not possible due to poor preservation and the incomplete nature of the material".[ 8]
'Plesiosaurus '
'P.' gulo
Western Kansas.[ 11]
KUVP 1329 (the original specimen consisted of "eleven cervical, thirteen dorsal, and seven or eight other vertebrae" but now only 3 vertebrae remain).[ 12]
An elasmosaurid associated with the remains of a mosasaur (likely Clidastes ), representing the stomach contents of the plesiosaur.[ 12]
Polycotylidae
Gen. et. sp. indeterminate
Morden area, Manitoba.[ 8]
Pembina Member.[ 8]
Many isolated vertebrae and partial skull remains.[ 8]
A polycotylid .
Serpentisuchops
S. pfisterae
Wyoming.[ 25]
Upper half of the upper member.[ 25]
"Specimen GPM5001".[ 25]
A polycotylid .
Styxosaurus
S. snowii
South Dakota.[ 8]
Sharon Springs Member.[ 8]
Complete specimen (SDSM 451).[ 8]
An elasmosaurid originally reported as Alzadasaurus pembertoni .
cf. S. snowii
Manitoba.[ 8]
Pembina Member.[ 8]
A specimen consisting of two femora, one humerus, two epipodials, fragments of the pelvic girdle and 14 vertebrae (MDM P83.02. 18).[ 8]
An elasmosaurid originally reported as cf. Alzadasaurus pembertoni .
Kansas.[ 20]
Sharon Springs Member.[ 20]
NJSM 15435.[ 20]
An elasmosaurid tentatively assigned to the genus Styxosaurus .
Trinacromerum
T. bonneri
Wyoming & South Dakota.[ 24]
Sharon Springs Member and Pembina Member.[ 8]
2 specimens: an adult (UNSM 50133) and a juvenile (UNSM 55810),[ 24] and several others.[ 8]
Now moved to the genus Martinectes .
T. cf. T. kirki
Manitoba.[ 8]
Pembina Member.[ 8]
TMP P84.162.3.[ 8]
A polycotylid .
T. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
Many poorly preserved specimens.[ 8]
A polycotylid .
Pterosaurs
Pterosaurs reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Pteranodon
P. longiceps
Kansas, Wyoming & South Dakota.[ 26]
Sharon Springs Member.[ 26]
A skull and multiple postcranial elements.[ 26]
A pteranodontid .
Turtles
Fish
Bony fish
Bony fish reported from the Pierre Shale Formation
Genus
Species
Presence
Stratigraphic position
Material
Notes
Images
Apsopelix
A. sp. cf. A. anglicus
Hughes County, South Dakota .[ 29]
Upper DeGrey Formation.[ 29]
SDSM 77482.[ 29]
A crossognathid .
Bananogmius
B. evolutus
Manitoba.[ 8]
Pembina Member.[ 8]
An articulated skull (MDM F75.05.06).[ 8]
Reassigned to the genus Pentanogmius .
B. sp.
Near Thornhill, Manitoba.[ 8]
Pembina Member.[ 8]
Skull and vertebral column (MMMN V82).[ 8]
Specimen originally identified as Ananogmius sp.[ 8]
Cimolichthys
C. nepaholica
Manitoba.[ 8]
Pembina Member.[ 8]
An aulopiform .
Cylindracanthus
Hyde County, South Dakota .[ 29]
Verendrye Formation.[ 29]
A rostral spine (SDSM 30638).[ 29]
Enchodus
E. gladiolus
Sharon Springs Member.[ 29]
An aulopiform .
E. petrosus
Manitoba.[ 8]
Pembina Member and Sharon Springs Member.[ 8] [ 29]
An aulopiform .
E. cf. saevus
Manitoba.[ 8]
Pembina Member.[ 8]
FMNH PF 5391 (a dentary, maxilla and palatine).[ 8]
Now a junior synonym of E. petrosus .
E. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
2 isolated vertebrae and isolated palatal fangs.[ 8]
An aulopiform .
Ichthyodectes
I. ctenodon
Manitoba.[ 8]
Pembina Member.[ 8]
Multiple mandibles and some skull and vertebral material.[ 8]
An ichthyodectid .
Ichthyodectidae
Gen. et. sp. indet.
Manitoba.[ 8]
Pembina Member.[ 8]
Vertebrae and partial caudal fins.[ 8]
An ichthyodectid not referrable to Xiphactinus but indistinguishable from other ichthyodectid genera.[ 8]
Pachyrhizodus
P. caninus
Manitoba.[ 8]
Pembina Member.[ 8]
A skull and anterior portions of the body (MDM F74.04.06), and a right dentary (FMNH PF 5397).[ 8]
A pachyrhizodontid .
P. minimus
Manitoba.[ 8]
Pembina Member.[ 8]
FMNH PF 5402.[ 8]
A pachyrhizodontid .
P. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
2 isolated vertebral centra (MMMN V73 ).[ 8]
A pachyrhizodontid .
P. sp. indet.
Hughes County, South Dakota .[ 29]
DeGrey Formation.[ 29]
SDSM 77481.[ 29]
A pachyrhizodontid .
Pentanogmius
P. evolutus
Manitoba.[ 8]
Pembina Member.[ 8]
An articulated skull (MDM F75.05.06).[ 8]
A plethodid , originally reported as Bananogmius evolutus .
Protosphyraena
P. gladius
Hyde County, South Dakota .[ 29]
DeGrey Formation.[ 29]
SDSM 66288 (major portion of pectoral fin).[ 29]
A pachycormid .
P. sp.
Manitoba.[ 8]
Pembina Member.[ 8]
A left premaxilla (FMNH PF 5400).[ 8]
Probably represents P. gladius .
Stratodus
S. apicalis
Manitoba.[ 8]
Pembina Member.[ 8]
An aulopiform .
Teleostei
Order, fam., gen. et. sp. indet.
Manitoba.[ 8]
Pembina Member.[ 8]
Mostly vertebrae, but also caudal fins and skulls in some specimens.[ 8]
Xiphactinus
X. audax
Manitoba and Lyman County, South Dakota .[ 8] [ 29]
Pembina Member and middle part of the Sharon Springs Member.[ 8] [ 29]
An ichthyodectid .
Cartilaginous fish
Marine vertebrates
Invertebrates
Annelids
Annelids reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Diploconcha
D. sp.
Wyoming.[ 1]
Arthropods
Arthropods reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Dioratiopus
D. hearttailensis
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A longodromitid crab.
Dromiopsis
D. kimberlyae
Butte County, South Dakota .[ 32]
Lower Pierre Shale.[ 32]
2 specimens.[ 32]
A dynomenid crab.
Heus
H. foersteri
Tepee Buttes , South Dakota.[ 33]
A raninid crab.
Hoplitocarcinus ?
H.? punctatus
Tepee Buttes , Colorado.[ 33]
A crab .
Hoploparia
H. mickelsoni
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A lobster .
Limulus
L. coffini
Fort Collins, Colorado .[ 34]
Rocky Ridge Sandstone Member.[ 34]
Thoracetron .[ 34]
A horseshoe crab .
Necrocarcinus
N. davisi
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A necrocarcinid crab.
Plagiophthalmus
P. bjorki
Tepee Buttes , South Dakota.[ 33]
A prosopid crab.
Protocallianassa
P. russelli
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A mud shrimp .
Raninella
R. manningi
Tepee Buttes , South Dakota.[ 33]
A raninid crab.
R. oaheensis
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A raninid crab.
Rugafarius
R. fredrichi
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A spiny lobster .
Xanthosia
X. elegans occidentalis
Butte County, South Dakota.[ 31]
Gammon Ferruginous Member.[ 31]
A xanthid crab.
Zygastrocarcinus
Z. cardsmithi
Carter County, Montana .[ 35]
Groat Sandstone Bed, Gammon Ferruginous Member.[ 35]
A homolid crab.
Bivalves
Bivalves reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Cataceramus ?
C.? barabini
Northeastern New Mexico.[ 6]
An inoceramid .
C.? cf. C. barabini
Northeastern New Mexico.[ 6]
An inoceramid .
Chlamys
C. (Chlamys) nebrascensis
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
A pectinid .
Cuspidaria
C. sp.
Bowman County, North Dakota .[ 36]
6 poorly-preserved, broken, decorticated specimens.[ 36]
A cuspidariid .
Cymbophora
C. cf. C. gracilis
Bowman County, North Dakota .[ 36]
9 complete specimens.[ 36]
A mactrid .
Eriphylopsis
E. gregaria
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
40 complete and incomplete specimens.[ 36]
An astartid .
Gervillia
G. sp.
Bowman County, North Dakota .[ 36]
One badly decorticated incomplete specimen.[ 36]
Inoceramus
I. (Endocostea) barabini
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
About 25 specimens.[ 36]
An inoceramid .
I. (Endocostea) fribrosa
Bowman County, North Dakota .[ 36]
4 small incomplete specimens.[ 36]
An inoceramid .
I. oblongus
West of Cimarron .[ 6]
An inoceramid .
I. sagensis
Bowman County, North Dakota .[ 36]
An inoceramid .
I. (Cremnoceramus) sp.
Bowman County, North Dakota .[ 36]
One decorticated incomplete specimen.[ 36]
An inoceramid .
I. sp. A
Bowman County, North Dakota .[ 36]
One specimen that is badly decorticated.[ 36]
An inoceramid .
I. sp. B
Bowman County, North Dakota .[ 36]
One slightly crushed specimen.[ 36]
An inoceramid .
Limopsis
L. parvula
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
About 40 specimens.[ 36]
A limopsid .
Lucina
L. (Lucina) occidentalis
Bowman County, North Dakota .[ 36]
14 specimens.[ 36]
A lucinid .
Mactra
M. sp.
Bowman County, North Dakota .[ 36]
4 broken incomplete molds.[ 36]
A mactrid .
Malletia
M. evansi
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
"7 badly decorticated incomplete specimens".[ 36]
A malletiid .
M. sp.
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
7 small, almost complete specimens.[ 36]
A malletiid .
Modiolus
M. meekii
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
2 small incomplete internal molds.[ 36]
Nemodon
N. sulcatinus
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
One badly weathered internal mold.[ 36]
A parallelodontid .
Nucula
N. sp.
Bowman County, North Dakota .[ 36]
"Five badly decorticated incomplete specimens".[ 36]
A nuculid .
Ostrea
O. congesta
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
3 slightly crushed fragments.[ 36]
An ostreid .
O. sp.
Bowman County, North Dakota .[ 36]
Numerous fragments.[ 36]
An ostreid .
Protocardia
P. (Leptocardia) rara
Bowman County, North Dakota .[ 36]
"10 complete, decorticated specimens".[ 36]
A cardiid .
Pteria
P. linguaeformis
Bowman County, North Dakota .[ 36]
About 15 broken specimens.[ 36]
A pteriid .
?Syncyclonema
?S. rigida
Bowman County, North Dakota .[ 36]
2 right valves.[ 36]
An entoliid .
Brachiopods
Brachiopods reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Lingula
L. sp.
Wyoming.[ 1]
Lower unnamed shale member.[ 1]
Cephalopods
Cephalopods reported from the Pierre Shale Formation
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Baculites
B. baculus
New Mexico.[ 6]
Upper & uppermost Pierre Shale.[ 6]
An ammonite .
B. cf. baculus
Bowman County, North Dakota .[ 36]
Baculites reesidei Range Zone.[ 36]
1 broken specimen.[ 36]
An ammonite .
B. compressus
At the Big Bend of the Missouri River , Buffalo County, South Dakota .[ 14]
Uppermost DeGrey Formation.[ 14]
Specimens associated with Globidens schurmanni .
B. cf. B. eliasi
Northeastern New Mexico.[ 6]
An ammonite .
B. grandis?
Bowman County, North Dakota .[ 36]
One large, crushed, badly weathered specimen.[ 36]
An ammonite .
B. reesidei
Bowman County, North Dakota .[ 36]
Baculites reesidei Zone.[ 36]
11 broken specimens.[ 36]
An ammonite .
B. sp.
Bowman County, North Dakota .[ 36]
Upper Baculites reesidei Zone.[ 36]
10 broken exfoliated specimens.[ 36]
An ammonite .
B. sp.
Northeastern New Mexico.[ 6] [ 28]
An ammonite .
Belemnitella
B. bulbosa
Upper Pierre Shale.[ 37]
A belemnite also found in the Fox Hills Formation .
B.? sp.
Meade County, South Dakota .[ 37]
Baculites compressus zone.[ 37]
1 specimen (BHI-7009).[ 37]
A belemnite .
Didymoceras
D. cochleatum
South Dakota & Wyoming.[ 38]
Gregory & Red Bird Silty members.[ 38]
Numerous fragments.[ 38]
An ammonite .
D. nebrascense
"Northwestern New Mexico through northeastern Montana".[ 39]
An ammonite .
D. sp.
Colfax County, New Mexico .[ 28]
An ammonite .
Enchoteuthis
E. cobbani
Meade & Pennington counties, South Dakota.[ 37]
Baculites cuneatus Zone & possibly the underlying B. compressus Zone.[ 37]
2 specimens.[ 37]
A coleoid , originally described as Tusoteuthis cobbani .[ 40]
E. melanae
Niobrara County, Wyoming .[ 37]
Baculites obtusus zone, Sharon Springs Member.[ 37]
Multiple specimens.[ 37]
A coleoid .
Eutrephoceras
E. dekayi
Colorado, Bowman County, North Dakota and Colfax County, New Mexico .[ 41] [ 28] [ 36]
Probably from the Baculites reesidei Zone.[ 36]
A nautiloid , one specimen from Colorado showing signs of mosasaur predation .[ 41]
E. montanaensis
Northeastern New Mexico.[ 6]
A nautiloid .
Exiteloceras
E. sp.
Bowman County, North Dakota .[ 36]
One fragmented body chamber.[ 36]
A nostoceratid ammonite .
Hoploscaphites
H. brevis
Bowman County, North Dakota .[ 36]
"Ten almost complete specimens and many fragments of early whorls".[ 36]
An ammonite .
H. crassus
Montana & Wyoming.[ 42]
An ammonite .
H. criptonodosus
Montana, Wyoming, Colorado, and possibly South Dakota.[ 43]
"Upper part of the Baculites baculus Zone and overlying B. grandis Zone".[ 43]
An ammonite also found in the Bearpaw Shale .
H. macer
Montana, Wyoming & Colorado.[ 43]
"Upper part of the Baculites baculus Zone and lower part of the overlying B. grandis Zone".[ 43]
An ammonite also found in the Bearpaw Shale .
H. cf. H. nicolleti
Bowman County, North Dakota .[ 36]
2 specimens.[ 36]
An ammonite .
H. nodosus
Near Raton, New Mexico .[ 6]
"30-45 m below the top of the Pierre Shale".[ 6]
An ammonite .
H. peterseni
Montana & Wyoming.[ 42]
An ammonite .
H. plenus
Montana, Wyoming & North Dakota.[ 42]
An ammonite .
H. quadrangularis
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
One broken shaft with aperture.[ 36]
An ammonite .
H. sp.
Bowman County, North Dakota .[ 36]
One broken specimen.[ 36]
An ammonite .
H. sp.
Colfax County, New Mexico .[ 28]
An ammonite .
Jeletzkytes
J. nodosus
At the Big Bend of the Missouri River , Buffalo County, South Dakota .[ 14]
Uppermost DeGrey Formation.[ 14]
Specimens associated with Globidens schurmanni.
Placenticeras
P. intercalere
Bowman County, North Dakota .[ 36]
"One decorticated specimen badly fractured by calcite crystal growth".[ 36]
An ammonite .
P. meeki
Colfax County, New Mexico and Bowman County, North Dakota .[ 28] [ 36]
Baculites reesidei Zone.[ 36]
An ammonite .
P. newberryi
Colfax County, New Mexico .[ 28]
An ammonite .
Ponteixites
P. robustus
Eastern Montana.[ 44]
Now a junior synonym of Rhaeboceras .
Rhaeboceras
R. burkholderi
Dawson County, Montana .[ 45]
Upper part of the Pierre Shale (Baculites eliasi zone).[ 45]
An ammonite .
R. cedarense
Dawson County, Montana .[ 45]
Baculites baculus/grandis zone.[ 45]
An ammonite .
R. robustus
Eastern Montana.[ 44]
An ammonite .
Scaphites
S. nodosus
Near Raton .[ 6]
"About 15 m below the top of the Pierre Shale".[ 6]
An ammonite .
Solenoceras
S. sp.
Bowman County, North Dakota .[ 36]
3 fragmented specimens.[ 36]
A nostoceratid ammonite .
Tusoteuthis
T. cobbani
Meade & Pennington counties, South Dakota.[ 37]
Baculites cuneatus Zone & possibly the underlying B. compressus Zone.[ 37]
2 specimens.[ 37]
Moved to the genus Enchoteuthis .[ 40]
T. longa
South Dakota .[ 37]
Baculites compressus Zone.[ 37]
A coleoid .
Echinoderms
Gastropods
Gastropods
Genus
Species
Location
Stratigraphic position
Material
Notes
Images
Anchura ?
A.? sp.
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
"One broken, badly decorticated, medium-sized specimen".[ 36]
Anisomyon
A. sexsulcatus?
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
"One badly decorticated specimen that is essentially an internal mold".[ 36]
A siphonariid .
At the Big Bend of the Missouri River , Buffalo County, South Dakota .[ 14]
Uppermost DeGrey Formation.[ 14]
A siphonariid , specimens associated with Globidens schurmanni .
Atira
A. nebrascensis
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
3 decorticated specimens.[ 36]
Cylichna
C. sp.
Bowman County, North Dakota .[ 36]
"Baculites reesidei Zone".[ 36]
"One weathered specimen so badly decorticated that it is essentially a mold of the interior".[ 36]
Cylindrotruncatum
C. cf. C. demursum
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
"One, small, broken, badly decorticated specimen".[ 36]
C. sp.
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
"Two medium-sized specimens; one in excellent condition and one internal mold".[ 36]
Drepanochilus
D. sp.
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
Approximately 20 specimens.[ 36]
Euspira
E. obliquata
Bowman County, North Dakota .[ 36]
Baculites reesidei Zone.[ 36]
25 nearly complete specimens.[ 36]
E. rectilabrum
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
4 fairly complete shells.[ 36]
Pyrifuses
P. sp.
Bowman County, North Dakota .[ 36]
1 weathered external mold.[ 36]
Striaticostatum ?
S.? sp.
Bowman County, North Dakota .[ 36]
Baculites reesidei Zone.[ 36]
One specimen.[ 36]
Turritella
T. macnaryensis?
Bowman County, North Dakota .[ 36]
Probably from the Baculites reesidei Zone.[ 36]
2 specimens.[ 36]
Scaphopods
References
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^ MacLachlan, M.E. (1976). "Lexicon of rock-stratigraphic units in Union, Colfax, Mora, and eastern Taos Counties, New Mexico" (PDF) . New Mexico Geological Society Field Conference Series . 27 : 205–215. Retrieved 14 October 2021 .
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^ a b c Larson, Neal (2020-01-01). "Large Scaphitid Ammonites (Hoploscaphites) from the Upper Cretaceous (Upper Campanian–Lower Maastrichtian) of North America: Endless Variation on a Single Theme" .
^ a b c d Landman, Neil H.; Kennedy, W. James; Larson, Neal L.; Grier, Joyce C.; Grier, James W.; Linn, Tom (February 2019). "Description of Two Species of Hoploscaphites (Ammonoidea: Ancyloceratina) from the Upper Cretaceous (Lower Maastrichtian) of the U.S. Western Interior" . Bulletin of the American Museum of Natural History . 2019 (427): 1–72. doi :10.1206/0003-0090.427.1.1 . ISSN 0003-0090 . S2CID 91263199 .
^ a b Grier, J. W.; Grier, J. C.; Larson, N. L.; Petersen, J. G. (2007-12-01). "Synonymy of the ammonite genus Ponteixites Warren with Rhaeboceras Meek" . Rocky Mountain Geology . 42 (2): 123–136. Bibcode :2007RMGeo..42..123G . doi :10.2113/gsrocky.42.2.123 . ISSN 1555-7332 .
^ a b c d Grier, Joyce C.; Grier, James W. (May 1998). "New findings of the ammonite Rhaeboceras, including a new species, from the Pierre Shale of eastern Montana" . Journal of Paleontology . 72 (3): 473–476. Bibcode :1998JPal...72..473G . doi :10.1017/S0022336000024227 . ISSN 0022-3360 . S2CID 130705667 .
^ a b c d e Blake, Daniel B.; Halligan, William; Larson, Neal L. (February 2018). "A new species of the asteroid genus Betelgeusia (Echinodermata) from methane seep settings, Late Cretaceous of South Dakota" . Journal of Paleontology . 92 (2): 196–206. Bibcode :2018JPal...92..196B . doi :10.1017/jpa.2017.96 . S2CID 134984198 .
^ a b c Thuy, Ben; Landman, Neil H.; Larson, Neal L.; Numberger-Thuy, Lea D. (2018-06-25). "Brittle-star mass occurrence on a Late Cretaceous methane seep from South Dakota, USA" . Scientific Reports . 8 (1): 9617. Bibcode :2018NatSR...8.9617T . doi :10.1038/s41598-018-27326-z . ISSN 2045-2322 . PMC 6018167 . PMID 29941907 .
^ a b Berry, Keith; Lucas, Spencer G. (2017-11-01). "An astropectinid sea star from the early Maastrichtian Pierre Shale in Southern Colorado, USA, and the extinction of inoceramid bivalves" . Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen . 286 (2): 159–168. doi :10.1127/njgpa/2017/0692 . ISSN 0077-7749 .
^ Hunter, Aaron W.; Larson, Neal L.; Landman, Neil H.; Oji, Tatsuo (May 2016). "Lakotacrinus brezinai n. gen. n. sp., a new stalked crinoid from cold methane seeps in the Upper Cretaceous (Campanian) Pierre Shale, South Dakota, United States" . Journal of Paleontology . 90 (3): 506–524. Bibcode :2016JPal...90..506H . doi :10.1017/jpa.2016.21 . ISSN 0022-3360 . S2CID 132578529 .
Cenozoic chronostratigraphy of Colorado
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Mesozoic chronostratigraphy of Colorado
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Paleozoic chronostratigraphy of Colorado
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Precambrian chronostratigraphy of Colorado
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