Euselachians from the freshwater deposits of the Hell Creek Formation of Montana

Todd D. Cook, Michael G. Newbrey, Donald B. Brinkman, James I. Kirkland

Research output: Chapter in Book/Report/Conference proceedingChapter

9 Citations (Scopus)

Abstract

An examination of freshwater euselachian fossils from the Maastrichtian lower and upper Hell Creek Formation, and the Bug Creek Anthills (Cretaceous-Paleogene boundary), and the early Paleocene (Puercan) Tullock Member of the Fort Union Formation of Montana, USA, revealed seven taxa: Lonchidion selachos, Protoginglymostoma estesi, Chiloscyllium, Restesia americana, Ischyrhiza avonicola, Myledaphus pustulosus n. sp., and Dasyatis (Dasyatidae). Squatirhina americana is redescribed to the new genus Restesia based on unique crown morphology. Dasyatis is only reported from the Paleocene. This is in contrast to the other collected taxa, which are only known from the Cretaceous. Ischyrhiza is not reported in our samples from the Hell Creek Formation despite earlier erroneous claims; however, the taxon is present in a sample from the Bug Creek Anthills. We suggest that this taxon infrequently moved into the freshwater rivers to forage. Lonchidion selachos occurs only in the upper Hell Creek Formation, and we hypothesize that the upper Hell Creek localities were deposited during a warm interval, as the paleodistribution of L. selachos shifted significantly to the north during warmer periods in the Santonian and Campanian. Of the taxa found in the Hell Creek Formation and the Bug Creek Anthills, only My ledaphus is found in Paleogene deposits; however, specimens are extremely rare. The occurrence of Myledaphus in the Paleogene is suggested to be due to the occurrence of reworked material.

Original languageEnglish (US)
Title of host publicationThrough the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas
EditorsGregory Wilson, William Clemens, John Horner, Joseph Hartman
Pages229-246
Number of pages18
DOIs
StatePublished - Feb 26 2014

Publication series

NameSpecial Paper of the Geological Society of America
Volume503
ISSN (Print)0072-1077

Fingerprint

Paleogene
Paleocene
creek
Santonian
Campanian
Maastrichtian
new genus
forage
fossil
Cretaceous
river
bug
material

All Science Journal Classification (ASJC) codes

  • Geology

Cite this

Cook, T. D., Newbrey, M. G., Brinkman, D. B., & Kirkland, J. I. (2014). Euselachians from the freshwater deposits of the Hell Creek Formation of Montana. In G. Wilson, W. Clemens, J. Horner, & J. Hartman (Eds.), Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas (pp. 229-246). (Special Paper of the Geological Society of America; Vol. 503). https://doi.org/10.1130/2014.2503(08)
Cook, Todd D. ; Newbrey, Michael G. ; Brinkman, Donald B. ; Kirkland, James I. / Euselachians from the freshwater deposits of the Hell Creek Formation of Montana. Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas. editor / Gregory Wilson ; William Clemens ; John Horner ; Joseph Hartman. 2014. pp. 229-246 (Special Paper of the Geological Society of America).
@inbook{db43e6a3217c479da412eda2bc4e52b2,
title = "Euselachians from the freshwater deposits of the Hell Creek Formation of Montana",
abstract = "An examination of freshwater euselachian fossils from the Maastrichtian lower and upper Hell Creek Formation, and the Bug Creek Anthills (Cretaceous-Paleogene boundary), and the early Paleocene (Puercan) Tullock Member of the Fort Union Formation of Montana, USA, revealed seven taxa: Lonchidion selachos, Protoginglymostoma estesi, Chiloscyllium, Restesia americana, Ischyrhiza avonicola, Myledaphus pustulosus n. sp., and Dasyatis (Dasyatidae). Squatirhina americana is redescribed to the new genus Restesia based on unique crown morphology. Dasyatis is only reported from the Paleocene. This is in contrast to the other collected taxa, which are only known from the Cretaceous. Ischyrhiza is not reported in our samples from the Hell Creek Formation despite earlier erroneous claims; however, the taxon is present in a sample from the Bug Creek Anthills. We suggest that this taxon infrequently moved into the freshwater rivers to forage. Lonchidion selachos occurs only in the upper Hell Creek Formation, and we hypothesize that the upper Hell Creek localities were deposited during a warm interval, as the paleodistribution of L. selachos shifted significantly to the north during warmer periods in the Santonian and Campanian. Of the taxa found in the Hell Creek Formation and the Bug Creek Anthills, only My ledaphus is found in Paleogene deposits; however, specimens are extremely rare. The occurrence of Myledaphus in the Paleogene is suggested to be due to the occurrence of reworked material.",
author = "Cook, {Todd D.} and Newbrey, {Michael G.} and Brinkman, {Donald B.} and Kirkland, {James I.}",
year = "2014",
month = "2",
day = "26",
doi = "10.1130/2014.2503(08)",
language = "English (US)",
isbn = "9780813725031",
series = "Special Paper of the Geological Society of America",
pages = "229--246",
editor = "Gregory Wilson and William Clemens and John Horner and Joseph Hartman",
booktitle = "Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas",

}

Cook, TD, Newbrey, MG, Brinkman, DB & Kirkland, JI 2014, Euselachians from the freshwater deposits of the Hell Creek Formation of Montana. in G Wilson, W Clemens, J Horner & J Hartman (eds), Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas. Special Paper of the Geological Society of America, vol. 503, pp. 229-246. https://doi.org/10.1130/2014.2503(08)

Euselachians from the freshwater deposits of the Hell Creek Formation of Montana. / Cook, Todd D.; Newbrey, Michael G.; Brinkman, Donald B.; Kirkland, James I.

Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas. ed. / Gregory Wilson; William Clemens; John Horner; Joseph Hartman. 2014. p. 229-246 (Special Paper of the Geological Society of America; Vol. 503).

Research output: Chapter in Book/Report/Conference proceedingChapter

TY - CHAP

T1 - Euselachians from the freshwater deposits of the Hell Creek Formation of Montana

AU - Cook, Todd D.

AU - Newbrey, Michael G.

AU - Brinkman, Donald B.

AU - Kirkland, James I.

PY - 2014/2/26

Y1 - 2014/2/26

N2 - An examination of freshwater euselachian fossils from the Maastrichtian lower and upper Hell Creek Formation, and the Bug Creek Anthills (Cretaceous-Paleogene boundary), and the early Paleocene (Puercan) Tullock Member of the Fort Union Formation of Montana, USA, revealed seven taxa: Lonchidion selachos, Protoginglymostoma estesi, Chiloscyllium, Restesia americana, Ischyrhiza avonicola, Myledaphus pustulosus n. sp., and Dasyatis (Dasyatidae). Squatirhina americana is redescribed to the new genus Restesia based on unique crown morphology. Dasyatis is only reported from the Paleocene. This is in contrast to the other collected taxa, which are only known from the Cretaceous. Ischyrhiza is not reported in our samples from the Hell Creek Formation despite earlier erroneous claims; however, the taxon is present in a sample from the Bug Creek Anthills. We suggest that this taxon infrequently moved into the freshwater rivers to forage. Lonchidion selachos occurs only in the upper Hell Creek Formation, and we hypothesize that the upper Hell Creek localities were deposited during a warm interval, as the paleodistribution of L. selachos shifted significantly to the north during warmer periods in the Santonian and Campanian. Of the taxa found in the Hell Creek Formation and the Bug Creek Anthills, only My ledaphus is found in Paleogene deposits; however, specimens are extremely rare. The occurrence of Myledaphus in the Paleogene is suggested to be due to the occurrence of reworked material.

AB - An examination of freshwater euselachian fossils from the Maastrichtian lower and upper Hell Creek Formation, and the Bug Creek Anthills (Cretaceous-Paleogene boundary), and the early Paleocene (Puercan) Tullock Member of the Fort Union Formation of Montana, USA, revealed seven taxa: Lonchidion selachos, Protoginglymostoma estesi, Chiloscyllium, Restesia americana, Ischyrhiza avonicola, Myledaphus pustulosus n. sp., and Dasyatis (Dasyatidae). Squatirhina americana is redescribed to the new genus Restesia based on unique crown morphology. Dasyatis is only reported from the Paleocene. This is in contrast to the other collected taxa, which are only known from the Cretaceous. Ischyrhiza is not reported in our samples from the Hell Creek Formation despite earlier erroneous claims; however, the taxon is present in a sample from the Bug Creek Anthills. We suggest that this taxon infrequently moved into the freshwater rivers to forage. Lonchidion selachos occurs only in the upper Hell Creek Formation, and we hypothesize that the upper Hell Creek localities were deposited during a warm interval, as the paleodistribution of L. selachos shifted significantly to the north during warmer periods in the Santonian and Campanian. Of the taxa found in the Hell Creek Formation and the Bug Creek Anthills, only My ledaphus is found in Paleogene deposits; however, specimens are extremely rare. The occurrence of Myledaphus in the Paleogene is suggested to be due to the occurrence of reworked material.

UR - http://www.scopus.com/inward/record.url?scp=84894268794&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84894268794&partnerID=8YFLogxK

U2 - 10.1130/2014.2503(08)

DO - 10.1130/2014.2503(08)

M3 - Chapter

AN - SCOPUS:84894268794

SN - 9780813725031

T3 - Special Paper of the Geological Society of America

SP - 229

EP - 246

BT - Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas

A2 - Wilson, Gregory

A2 - Clemens, William

A2 - Horner, John

A2 - Hartman, Joseph

ER -

Cook TD, Newbrey MG, Brinkman DB, Kirkland JI. Euselachians from the freshwater deposits of the Hell Creek Formation of Montana. In Wilson G, Clemens W, Horner J, Hartman J, editors, Through the End of the Cretaceous in the Type Locality of the Hell Creek Formation in Montana and Adjacent Areas. 2014. p. 229-246. (Special Paper of the Geological Society of America). https://doi.org/10.1130/2014.2503(08)