Eutaw Formation

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The Eutaw Formation is a geological formation in North America, within the U.S. states of Alabama, Georgia, and Mississippi. The strata date from the late Coniacian to the early Santonian stage of the Late Cretaceous.[1] It consists of the upper Tombigbee Sand Member and an unnamed lower member. Dinosaur, mosasaur, and pterosaur remains have been recovered from the Eutaw Formation.[2][3]

Eutaw Formation
Stratigraphic range: Upper Cretaceous
TypeGeological formation
Sub-unitsTombigbee Sand Member, Ingersoll Shale
UnderliesAustin Group and Mooreville Chalk Formation
OverliesTuscaloosa Group
Thickness40 m (130 ft) to 120 m (390 ft)
Lithology
PrimaryGlauconitic sandstone
Location
RegionAlabama, Georgia, Mississippi
CountryUnited States
Type section
Named forEutaw, Alabama

Vertebrate paleofauna

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Cartilaginous fish

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Cartilaginous fish of the Eutaw Formation
Taxa Species State Stratigraphic position Abundance Notes Images

Archaeolamna

A. kopingensis[4]

Alabama[4]

A lamniform shark

 
Tooth of Cretoxyrhina mantelli
 
Ischyrhiza mira rostral spines
 
Teeth of Scapanorhynchus texanus
 
Squalicorax falcatus

Borodinopristis

B. schwimmeri[4]

Alabama[4]

A sclerorhynchid

Brachyrhizodus

B. mcnultyi[4]

Alabama[4]

Myliobatids

B. wichitaensis[4]

Carcharias

C. sp.[4]

Alabama[4]

A lamniform shark

Cantioscyllium

C. globidens[4]

Alabama[4]

Carpet sharks

C. decipiens (=C. meyeri or C. saginatus?)[4]

Chiloscyllium

C. greeni[4]

Alabama[4]

A hemiscylliid

Cretodus

C. semiplicatus[4]

Alabama[4]

A lamniform shark

Cretalamna

C. appendiculata[4]

Alabama[4]

Otodontids

C. serrata[4]

Cretoxyrhina

C. mantelli[4]

Alabama[4]

A lamniform shark

Edaphodon

E. sp.[4]

Alabama[4]

A chimaera

Heterodontus?

H. sp.[4]

Alabama[4]

A heterodontiform

Hybodus

H. sp.[4]

Alabama[4]

A hybodontid

Ischyrhiza

I. mira[4]

Alabama[4]

A rajiform

Lissodus (=Lonchidion?)

L. sp.[4]

Alabama[4]

A hybodontid

Paranomotodon

P. angustidens[4]

Alabama[4]

A lamniform shark

Pseudocorax

P. laevis[4]

Alabama[4]

A lamniform shark

Pseudohypolophus (=Brachyrhizodus?)

P. mcnultyi[4]

Alabama[4]

A rajiform

Ptychodus

P. mortoni[4]

Alabama[4]

Ptychodontids

P. polygyrus[4]

P. rugosus[4]

Ptychotrygon

P. triangularis (=P. vermiculata and/or P. chattahoochiensis?)[4]

Alabama[4]

A ptychotrygonid

Rajiformes indet.[4]

Alabama[4]

Scapanorhynchus

S. raphiodon[4]

Alabama[4]

Lamniform sharks

S. texanus[4]

Sclerorhynchus?

S. sp.[4]

Alabama[4]

A rajiform

Squalicorax

S. falcatus[4]

Alabama[4]

Lamniform sharks

S. kaupi[4]

S. pristodontus[4]

Squatina

S. hassei[4]

Alabama[4]

A squatinid

Bony fish

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Bony fish of the Eutaw Formation
Taxa Species State Stratigraphic position Abundance Notes Images

Albula

A. dunklei[4]

Alabama[4]

A bonefish

 
Enchodus petrosus
 
Protosphyraena
 
Stratodus
 
Xiphactinus audax

Anomoeodus

A. phaseolus[4]

Alabama[4]

A pycnodontid

Atractosteus

A. sp.?[4]

Alabama[4]

A gar

Bananogmius

B. sp.[4]

Alabama[4]

A plethodid

Belonostomus

B. sp.[4]

Alabama[4]

An aspidorhynchiform

Enchodus

E. petrosus[4]

Alabama[4]

An enchodontid

Hadrodus

H. priscus[4]

Alabama[4]

A pycnodontid

Lepisosteus

L. sp.[4]

Alabama[4]

A gar

Mawsonia

M. sp.[4]

Alabama[4]

A coelacanthiform fish

Phacodus

P. puncatatus[4]

Alabama[4]

A pycnodontiform

Protosphyraena

P. sp.[4]

Alabama[4]

A pachycormiform

Stratodus

S. apicalis[4]

Alabama[4]

An aulopiform

Xiphactinus

X. audax[4]

Alabama[4]

An ichthyodectid

Turtles

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Turtles of the Eutaw Formation
Taxa Species State Stratigraphic position Abundance Notes Images

Chedighaii

C. barberi[4]

Alabama[4]

A bothremydid

 
Protostega gigas

Protostega

P. gigas[4]

Alabama[4]

A protostegid

Thinochelys

T. sp.[4]

Alabama[4]

Toxochelys

T. sp.[4]

Alabama[4]

Trionychidae indet.[4]

Alabama[4]

Plesiosaurs

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Plesiosaurs of the Eutaw Formation
Taxa Species State Stratigraphic position Abundance Notes Images

Discosaurus

D. vetustus[4]

Alabama[4]

An elasmosaurid

 
Vertebrae of D. vestutus

Elasmosauridae indet.[4]

Alabama[4]

Mosasaurs

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Mosasaurs of the Eutaw Formation
Taxa Species State Stratigraphic position Abundance Notes Images

Clidastes

Clidastes sp.[2][4]

Alabama[2][4]

A mosasaurine

 
Eonatator sternbergii
 
Platecarpus tympaniticus
 
Tylosaurus proriger skull

Eonatator

E. sternbergii[2][5]

Alabama[2]

A halisaurine

  1. E. sternbergii was formerly classified as Halisaurus sternbergii

Globidens

G. alabamaensis[4]

Alabama[4]

A mosasaurine

Platecarpus

P. tympaniticus[2][4]

Alabama[2][4]

A plioplatecarpine

Plioplatecarpus

P. sp.[4]

Alabama[4]

A plioplatecarpine

Selmasaurus

S. russelli[2][4]

Alabama[2][4]

A plioplatecarpine

Tylosaurus

T. nepaeolicus[4]

Alabama[4]

Tylosaurines

T. proriger[4]

Crocodylians

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Crocodylians of the Eutaw Formation
Genus Species State Stratigraphic position Abundance Notes Images

Borealosuchus

B. sp.[4]

Alabama[4]

An eusuchian

 
A skull of Deinosuchus

Deinosuchus

D. rugosus?[4]

Alabama[4]

An alligatoroid

Leidyosuchus

L. sp.[4]

Alabama[4]

An alligatoroid

Ornithodires

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Dinosaur feathers have been found in the Ingersoll Shale of Georgia, which is a subunit of the Eutaw Formation.[3] Indeterminate hadrosaurid remains have been found in Mississippi.[6] Ornithomimosaurs of medium-size and large-size have also been unearthed in Mississippi.[7]

Ornithodires of the Eutaw Formation
Genus Species State Stratigraphic position Abundance Notes Images

Lophorhothon

L. atopus[4]

Alabama[4]

A hadrosauromorph dinosaur

 
Illustration of a fossil of Lophorhothon
 
Pteranodon sp.

Pteranodon

Indeterminate

Georgia[3]

A pteranodontid pterosaur

See also

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References

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  1. ^ Liu, Kaiyu. "Facies Changes of the Eutaw Formation (Coniacian-Santonian), Onshore to Offshore, Northeastern Gulf of Mexico Area". Department of Geological Sciences. University of Alabama. Retrieved 2009-02-10.
  2. ^ a b c d e f g h i 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. S2CID 130280406.
  3. ^ a b c "Coastal Plain Geologic Province". The New Georgia Encyclopedia. Georgia Humanities Council and the University of Georgia Press. 2007-08-30. Retrieved 2009-02-10.
  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 z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf bg bh bi bj bk bl bm bn bo bp bq br bs bt bu bv bw bx by bz ca cb cc cd ce cf cg ch ci cj ck cl cm cn co cp cq cr cs ct cu cv cw cx cy cz da db dc dd de df dg dh di dj dk dl dm 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.
  5. ^ Bardet N, Suberbiola P, Iarochene M, Bouyahyaoui F, Bouya B, Amaghzaz M (2002). "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.
  6. ^ Kaye, John M.; Russell, Dale A. (January 1973). "The Oldest Record of Hadrosaurian Dinosaurs in North America". Journal of Paleontology. 47 (1): 91–93. JSTOR 1302869.
  7. ^ Chinzorig, Tsogtbaatar; Cullen, Thomas; Phillips, George; Rolke, Richard; Zanno, Lindsay E. (2022-03-25). "Large-bodied ornithomimosaurs inhabited Appalachia during the Late Cretaceous of North America": 2022.03.25.485782. doi:10.1101/2022.03.25.485782. S2CID 247749395. {{cite journal}}: Cite journal requires |journal= (help)