Bladen Formation
Geologic formation in North Carolina
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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]
| Bladen Formation | |
|---|---|
| Stratigraphic range: Middle Campanian ~ | |
| Type | Formation |
| Unit of | Black Creek Group |
| Underlies | Donoho Creek Formation, Peedee Formation |
| Overlies | Tar Heel/Coachman Formation |
| Lithology | |
| Primary | Sandstone, siltstone |
| Location | |
| Region | North Carolina, South Carolina |
| Country | United States |
| Type section | |
| Named for | Bladen County, North Carolina |
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
| Hybodonts of the Bladen Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | |
| Lonchidion | L. babulskii | Elizabethtown, NC | A lonchidiid. |  | |
| Meristodonoides | M. novojerseyensis | Elizabethtown, NC | A hybodontid. |  | |
| M. sp. | |||||
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. | _marrocanus_Arambourg_1935_-_Dalpiazia_stromeri_Checcia-Rispoli,_1933_7100.5122.jpg) | |
| 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
| Bony fish of the Bladen Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | |
| Albula | A. sp. | Elizabethtown, NC | A bonefish. |  | |
| Anomoeodus | A. phaseolus | Elizabethtown, NC | A pycnodontid pycnodont. |  | |
| Cylindracanthus | C. sp | Elizabethtown, NC | A fish of uncertain affinities. |  | |
| Enchodus | E. cf. petrosus | Elizabethtown, NC | An enchodontid aulopiform. |  | |
| Hadrodus | H. priscus | Elizabethtown, NC | A hadrodontid fish (considered a pycnodont or a semionotiform) |  | |
| Lepisosteus | L. sp. | Elizabethtown, NC | A gar. |  | |
| Paralbula | P. casei | Elizabethtown, NC | A phyllodontid elopomorph. | ||
| Protosphyraena | P. sp. | Elizabethtown, NC | A pachycormid. |  | |
| Xiphactinus | X. vetus | Elizabethtown, NC | An ichthyodectid ichthyodectiform. |  | |
Amphibians
| Amphibians of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Albanerpetontidae indet. | Elizabethtown, NC | An albanerpetontid.[12][13] | ||||
Reptiles
Dinosaurs
Based on Brownstein (2018):[14]
| Dinosaurs of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| "Coelosaurus" (="Ornithomimus") | "C." sp. | Elizabethtown, NC | An ornithomimosaur. |  | ||
| Hadrosauridae indet. | Elizabethtown, NC | A hadrosaur. | ||||
| Tyrannosauroidea indet. | Elizabethtown, NC | A tyrannosauroid. | ||||
Crocodylomorphs
| Crocodylomorphs of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Borealosuchus | B. sp. | Elizabethtown, NC
Quinby, SC |
A eusuchian. |  | ||
| Deinosuchus | D. rugosus | Elizabethtown, NC
Quinby, SC |
An alligatoroid, one of the largest known crocodilians. |  | ||
| Gavialoidea indet. | Quinby, SC | A gavialoid. | ||||
Turtles
| Turtles of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Bothremys | B. sp. | Elizabethtown, NC | A bothremydid side-necked turtle. | |||
| Chedighaii | C. sp. | Elizabethtown, NC | A bothremydid side-necked turtle. | |||
| Euclastes | E. wielandi | Quinby, SC | A pancheloniid sea turtle. |  | ||
| "Trionyx" | "T." halophilus | Quinby, SC | A stem-softshell turtle, likely not an actual member of the genus Trionyx. Species names are nomina dubia. | |||
| "T." priscus | Quinby, SC | |||||
| "T." sp. | Elizabethtown, NC | |||||
Plesiosaurs
| Plesiosaurs of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Elasmosauridae indet. | Elizabethtown, NC
Quinby, SC |
An elasmosaurid. | ||||
Squamates
| Squamates of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Coniophis | C. sp. | Elizabethtown, NC | An aquatic snake.[15] |  | ||
| Tylosaurus | T. sp. | Elizabethtown, NC | A tylosaurine mosasaur. |  | ||
Mammals
| Mammals of the Bladen Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Notes | Images | ||
| Cimolomys | C. sp. | Elizabethtown, NC | A multituberculate. |  | ||
