The Bladen Formation is a geologic formation from the Late Cretaceous (middle Campanian) of North Carolina and South Carolina, USA. It is known for a plethora of terrestrial and aquatic vertebrate fossils, including dinosaurs and mosasaurs.[1] It appears to be roughly concurrent with the Tuscaloosa Formation of Alabama.[2]
Unlike many other Cretaceous geologic formations from eastern North America, which were deposited in entirely marine environments, the Bladen Formation appears to have been deposited in a former river delta in an estuarine habitat, allowing for a mixture of freshwater, terrestrial, and marine fauna.[3] An important locality is the former Bladen County landfill annex in Elizabethtown, North Carolina, which contains the richest known fauna from the formation.[4][5] Another notable locality is near Quinby in Florence County, South Carolina, which also appears to have been deposited in a nonmarine environment with minor marine influence.[6]
It is deposited as a thin layer over the Tar Heel/Coachman Formation, which is often confused with. In North Carolina, it underlies the Maastrichtian-aged Peedee Formation, while in South Carolina it underlies the slightly younger Campanian-aged Donoho Creek Formation.[7]
Vertebrate paleobiota
Based on Crane (2011), Schwimmer et al (2015) and the Paleobiology Database:[3][6][8]
Cartilaginous fish
Based on Crane (2011) and Case et al (2019):[3][9]
The chondrichthyan biota closely resembles that of the Aguja Formation from Texas.[9]
Hybodonts
Sharks
| Sharks of the Bladen Formation
|
| Genus
|
Species
|
Location
|
Notes
|
Images
|
| Archaeolamna
|
A. kopingensis
|
Elizabethtown, NC
|
An archaeolamnid mackerel shark.
|
|
| Cantioscyllium
|
C. clementsi
|
Elizabethtown, NC
|
A nurse shark. Type locality of this species.
|
|
| Cretalamna
|
C. appendiculata
|
Elizabethtown, NC
|
A megatooth shark.
|
|
| C. sp.
|
| Cretorectolobus
|
C. sp.
|
Elizabethtown, NC
|
A wobbegong.
|
|
| Galeorhinus
|
G. sp.
|
Elizabethtown, NC
|
A relative of the school shark.
|
|
| Plicatoscyllium
|
P. globidens
|
Elizabethtown, NC
|
A nurse shark.
|
|
| Protolamna
|
P. borodini
|
Elizabethtown, NC
|
An eoptolamnid mackerel shark.
|
|
| Scapanorhynchus
|
S. texanus
|
Elizabethtown, NC
|
A goblin shark.
|
|
| Squalicorax
|
S. kaupi
|
Elizabethtown, NC
|
A crow shark.
|
|
| S. cf. S. pristodontus
|
| Squatina
|
S. sp.
|
Elizabethtown, NC
|
An angelshark. Sometimes assigned to the dubious species S. hassei.[9]
|
|
Rays
| Rays of the Bladen Formation
|
| Genus
|
Species
|
Location
|
Notes
|
Images
|
| Anoxypristis
|
A. sp.
|
Elizabethtown, NC
|
A sawfish.
|
|
| Borodinopristis
|
B. schwimmeri
|
Elizabethtown, NC
|
A sclerorhynchid sawskate. Type locality of B. shannoni.[10]
|
|
| B. shannoni
|
| Brachyrhizodus
|
B. wichitaensis
|
Elizabethtown, NC
|
An eagle ray.
|
|
| Dasyatis
|
D. cf. commercensis
|
Elizabethtown, NC
|
A whiptail stingray.
|
|
| Ischyrhiza
|
I. avonicola
|
Elizabethtown, NC
|
A sclerorhynchid sawskate.
|
|
| I. mira
|
| Onchopristis
|
O. sp.
|
Elizabethtown, NC
|
An onchopristid sawskate.
|
|
| Ptychotrygon
|
P. triangularis
|
Elizabethtown, NC
|
A ptychotrygonid sawskate.
|
|
| P. vermiculata
|
| Protoplatyrhina
|
P. sp.
|
Elizabethtown, NC
|
A hypsobatid ray.[11]
|
|
| Pseudohypolophus
|
P. ellipsis
|
Elizabethtown, NC
|
A guitarfish.
|
|
| Rhinobatos
|
R. casieri
|
Elizabethtown, NC
|
A guitarfish.
|
|
| Rhombodus
|
R. binkhorsti
|
Elizabethtown, NC
|
A rhombodontid ray.
|
|
| R. laevis
|
| Schizorhiza
|
S. sp.
|
Elizabethtown, NC
|
A schizorhizid sawskate.
|
|
Bony fish
Amphibians
Reptiles
Dinosaurs
Based on Brownstein (2018):[14]
Crocodylomorphs
Turtles
Plesiosaurs
Squamates
Mammals
See also
References
- ^ Various Contributors to the NCSM, et al. 2020. "NCSM Collection: Paleontology Database."
- ^ "Geolex — Bladen publications". ngmdb.usgs.gov. Retrieved 2024-11-13.
- ^ a b c Crane, Cynthia Danielle (2011). VERTEBRATE PALEONTOLOGY AND TAPHONOMY OF THE LATE CRETACEOUS (CAMPANIAN) BLADEN FORMATION, BLADEN COUNTY, NORTH CAROLINA (Thesis).
- ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-11-13.
- ^ Crane, Cynthia Danielle (2011). Vertebrate paleontology and taphonomy of the late Cretaceous (Campanian) Bladen Formation, Bladen County, North Carolina (Thesis).
- ^ a b Schwimmer, David R.; Sanders, Albert E.; Erickson, Bruce R.; Weems, Robert E. (2015). "A Late Cretaceous Dinosaur and Reptile Assemblage from South Carolina, Usa". Transactions of the American Philosophical Society. 105 (2): i–157. ISSN 0065-9746. JSTOR 24398224.
- ^ "Geolex — Bladen publications". ngmdb.usgs.gov. Retrieved 2024-11-13.
- ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-11-15.
- ^ a b c Case, Gerald R.; Cook, Todd D.; Kightlinger, Taylor (2019-07-31). "A description of a middle Campanian euselachian assemblage from the Bladen Formation of North Carolina, USA". Vertebrate Anatomy Morphology Palaeontology. 7: 69–82. doi:10.18435/vamp29345. ISSN 2292-1389.
- ^ Case, Gerard R.; Cook, Todd D.; Wilson, Mark V.H.; Borodin, Paul D. (2012). "A new species of the sclerorhynchid sawfish Borodinopristis from the Campanian (Upper Cretaceous) of North Carolina, USA". Historical Biology. 24 (6): 592–597. doi:10.1080/08912963.2012.663367. ISSN 0891-2963.
- ^ "Protoplatyrhina sp. | Shark-References". shark-references.com. Retrieved 2024-11-15.
- ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-11-13.
- ^ Gardner, James D.; DeMar, David G. (2013-12-01). "Mesozoic and Palaeocene lissamphibian assemblages of North America: a comprehensive review". Palaeobiodiversity and Palaeoenvironments. 93 (4): 459–515. doi:10.1007/s12549-013-0130-z. ISSN 1867-1608.
- ^ Brownstein, Chase D. (2018-02-08). "The biogeography and ecology of the Cretaceous non-avian dinosaurs of Appalachia". Palaeontologia Electronica. Retrieved 2024-11-15.
- ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-11-13.