The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of the Late Cretaceous.[1] The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment. It is a unit of the Selma Group and consists of the upper Arcola Limestone Member and an unnamed lower member.[2] Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation.[1][2][3]

Mooreville Chalk
Stratigraphic range: Upper Cretaceous
TypeGeological formation
Unit ofSelma Group
Sub-unitsArcola Limestone Member
UnderliesDemopolis Chalk Formation
OverliesEutaw Formation
Lithology
PrimaryChalk
Location
RegionAlabama, Mississippi
CountryUnited States

Fish

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Cartilaginous fish

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Cartilaginous fish of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Cretolamna

C. appendiculata[3]

A lamniform

 
Cretoxyrhina mantelli
 
Squalicorax sp.

Cretoxyrhina

C. mantelli[3]

A lamniform

Edaphodon

E. barberi[4]

Chimaeriforms

E. mirificus[4]

Ischyodus

I. williamsae[4]

A chimaeriform

Odontaspis

O. cuspidata

A lamniform

Propenser

P. hewletti[4]

Lamniformes

Ptychodus

P. mammillaris[4]

?Neoselachian incertae sedis

P. mortoni[3]

P. polygyrus[4]

Pseudocorax

P. affinis[4]

Lamniformes

P. laevis[3]

Serratolamna

S. serrata[3]

A lamniform

Scapanorhynchus

S. rhaphiodon[4]

Lamniformes

S. texanus[3]

Squalicorax

S. falcatus[4]

Lamniformes

S. kaupi[3]

Bony fish

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Bony fish of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Albula

A. dunklei[4]

An albuliform

 
Enchodus petrosus
 
Saurodon leanus
 
Xiphactinus audax

Bananogmius

B. crieleyi[4]

A tselfatiiform

Cimolichthys

C. nepaholica[4]

An aulopiform

Enchodus

E. petrosus[4][3]

An aulopiform

E. saevus[4]

Hoplopteryx

Hoplopteryx sp.[4]

A trachichthyiform

Ichthyodectes

I. ctenodon[4]

An ichthyodectiform

Moorevillia

M. hardi[4]

A tselfatiiform

Pachyrhizodus

P. caninus[4]

A crossognathiform

Protosphyraena

P. gladius[3]

A pachycormid

Saurodon

S. leanus[4]

An ichthyodectiform

Stratodus

S. apicalis[4]

An aulopiform

Xiphactinus

X. audax[4]

An ichthyodectiform

Reptiles

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Dinosaurs

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Indeterminate hadrosaurid, nodosaurid, dinosaur egg, and ornithomimosaur fossils are known from Mooreville Chalk outcrops in Alabama.[1] The nodosaurid remains most likely belong to a new taxon.[5]

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Dinosaurs reported from the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Material Notes Images

Angelinornis

A. antecessor

A. antecessor was originally described as Plegadornis antecessor, but the generic name Plegadornis was preoccupied, so the genus Angelinornis was erected to contain the species. It was later demonstrated that Angelinornis was a junior synonym of Ichthyornis, although the new combination I. antecessor was held to be valid for a while following the sinking of Angelinornis into Ichthyornis. Later the species would later be considered a junior synonym of the Ichthyornis type species, I. dispar.[1]

 
Eotrachodon
 
Ichthyornis dispar
 
Saurornitholestes

Eotrachodon[6]

E. orientalis

A hadrosaurid known from a nearly complete skeleton and nearly complete skull.

Halimornis[1][2]

H. thompsoni[1][2]

"Vertebrae and limb elements."[7]

An enantiornithine

Ichthyornis[1][2]

I. antecessor

The species I. antecessor was made the type species of the genus Angelinornis in 1962. Later, I. antecessor and Angelinornis were shown to be junior synonyms of the Ichthyornis type species, I. dispar[1]

I. dispar[1][2]

An ichthyornithine.

Lophorhothon[1][3]

L. atopus[1][3]

A primitive species of hadrosaurid known from only a few skull fragments.[1]

Saurornitholestes[5] S. sp. A dromaeosaurid.

Plegadornis

P. antecessor

The name Plegadornis antecessor was applied to a fossil believed to represent a new bird species, but the generic name Plegadornis was preoccupied, so the genus Angelinornis was erected to contain the "new" species. It was later demonstrated that Angelinornis was a junior synonym of Ichthyornis, although the new combination I. antecessor was held to be valid for a while following the sinking of Angelinornis into Ichthtyornis. Later the species would later be considered a junior synonym of the Ichthyornis type species, I. dispar.[1]

Mosasaurs

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Mosasaurs of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Clidastes

C. liodontus[4]

Mosasaurines

 
Clidastes propython
 
Eonatator sternbergii
 
Globidens alabamaensis
 
Platecarpus tympaniticus
 
Selmasaurus russelli
 
Tylosaurus proriger

C. "moorevillensis"[3]

C. propython[4][3]

Ectenosaurus E. shannoni[8] A plioplatecarpine

Eonatator

E. sternbergi (sic)[3][9]

A halisaurine E. sternbergii was formerly classified as Halisaurus sternbergii[10]

E. zangerli[11]

Globidens

G. alabamaensis[3]

A mosasaurine

Mosasaurus

M. missouriensis[3]

A mosasaurine

Platecarpus

P. tympaniticus[3]

A plioplatecarpine

Prognathodon

P. rapax[4]

A mosasaurine

Selmasaurus

S. russelli[3]

A plioplatecarpine

Tylosaurus

T. proriger[4]

A tylosaurine

Plesiosaurs

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Very rare elasmosaurs are present in this formation.[3]

Plesiosaurs of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Trinacromerum

Trinacromerum sp.[3]

Polycotylids

 
Trinacromerum sp.

Pterosaurs

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Pterosaurs of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Pteranodon

Pteranodon sp.[3]

Pteranodontids.

 
Pteranodon sp.

Turtles

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Turtles of the Mooreville Chalk Formation
Genus Species Location Stratigraphic position Abundance Notes Images

Bothremys

B. barberi[3]

A pelomedusid.

 
Protostega gigas

Corsochelys

C. haliniches

A dermochelyid.

Protostega

P. gigas[3]

A protostegid.

Toxochelys

T. moorevillensis[3]

A toxochelyid.

See also

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References

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  1. ^ a b c d e f g h i j k l m n o p Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. ISBN 0-520-24209-2.
  2. ^ a b c d e f Chiappe, Luis; Lamb, James P.; Ericson, PER G. P. (2002). "New enantiornithine bird from the marine Upper Cretaceous of Alabama". Journal of Vertebrate Paleontology. 22 (1): 170–174. doi:10.1671/0272-4634(2002)022[0170:NEBFTM]2.0.CO;2.
  3. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Kiernan, Caitlin R. (2002). "Stratigraphic distribution and habitat segregation of mosasaurs in the Upper Cretaceous of western and central Alabama, with an historical review of Alabama mosasaur discoveries". Journal of Vertebrate Paleontology. 22 (1): 91–103. doi:10.1671/0272-4634(2002)022[0091:SDAHSO]2.0.CO;2.
  4. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Applegate, Shelton P.; Dale E. Russell (1970). The Vertebrate Fauna of the Selma Formation of Alabama. Part VII. Part VIII. The Mosasaurs The Fishes. Chicago: Field Museum of Natural History. pp. 387–430. OCLC 50419737.
  5. ^ a b Brownstein, Chase D. (2018-02-08). "The biogeography and ecology of the Cretaceous non-avian dinosaurs of Appalachia". Palaeontologia Electronica. 21 (1): 1–56. doi:10.26879/801. ISSN 1094-8074.
  6. ^ Albert Prieto-Márquez, Gregory M. Erickson & Jun A. Ebersole, 2016, "A primitive hadrosaurid from southeastern North America and the origin and early evolution of ‘duck-billed’ dinosaurs", Journal of Vertebrate Paleontology DOI:10.1080/02724634.2015.1054495
  7. ^ "Table 11.1," in Weishampel, et al. (2004). Page 213.
  8. ^ Kiernan, Caitlin R.; Ebersole, Jun A. (2023). "Two new plioplatecarpine mosasaurs (Mosasauridae; Plioplatecarpinae) of the genus Ectenosaurus from the Upper Cretaceous of North America". PaleoBios. 40 (13). doi:10.5070/P9401362375. ISSN 0031-0298.
  9. ^ Kejiri, T.; Ebersole, J.A.; Blewitt, H.L.; Ebersole, S.M. (2013). "An Overview of Late Cretaceous Vertebrates from Alabama". Bulletin of the Alabama Museum of Natural History. 31 (1): 46–71.
  10. ^ Bardet N, Suberbiola P, Iarochene M, Bouyahyaoui F, Bouya B, Amaghzaz M (2005). "A new species of Halisaurus from the Late Cretaceous phosphates of Morocco, and the phylogenetical relationships of the Halisaurinae (Squamata: Mosasauridae)". Zoological Journal of the Linnean Society. 143 (3): 447–472. doi:10.1111/j.1096-3642.2005.00152.x.
  11. ^ "The relationships of Alabama halisaurine mosasaurs". Academia.edu. Retrieved 10 December 2021.