Tar Heel/Coachman Formation

The Tar Heel Formation, also known as the Coachman Formation in South Carolina, is a Late Cretaceous (early to middle Campanian-aged) geologic formation in North Carolina and South Carolina, USA. It preserves fossils, including amber dating back to the Cretaceous period. A locality known as Phoebus Landing, has been dated to 78.5-77.1 Ma, and the formation has been overall dated to the early Campanian based on fossil pollen.^[1][2][3]

Tar Heel/Coachman Formation
Stratigraphic range: Early-Middle Campanian ~83.2–77.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Formation
Unit of	Black Creek Group
Underlies	Bladen Formation
Overlies	Middendorf Formation
Lithology
Primary	Siltstone, sandstone
Location
Coordinates	34.6°N 78.5°W / 34.6; -78.5
Approximate paleocoordinates	35.0°N 50.2°W / 35.0; -50.2
Region	North Carolina  South Carolina
Country	United States
Type section
Named for	Tar Heel, North Carolina

Likely deposited in a nearshore coastal environment representing a lower shoreface, it contains a high diversity of vertebrate remains. It has one of the most diverse dinosaur faunas known from the former landmass of Appalachia, the majority of which are known from two sites: Phoebus Landing along the Cape Fear River in Bladen County, North Carolina, as well as Stokes Quarry in Darlington County, South Carolina.^[4][5][6]

Fossil pollen grains suggest a subtropical to warm, moist temperate climate for the region, with an ecosystem largely dominated by flowering plants.^[3] The Tar Heel/Coachman Formation appears to be roughly concurrent with the Marshalltown Formation of New Jersey, which preserves a similar fauna.^[4]

Paleobiota

Cartilaginous fish

Cartilaginous fish of the Tar Heel/Coachman Formation
Genus	Species	Location	Notes	Images
Ischyrhiza	I. mira		An extinct genus of sawfish	Squalicorax kaupi Cretolamna Modern sand tiger shark.
Squalicorax	S. falcatus S. kaupi S. pristodontus S. bassanii		An anacorid shark. Includes a coprolite potentially assignable to S. kaupi, containing the vertebrae of a baby turtle.[7]
Hybodus	H. sp.		A hybodontid shark
Scapanorhynchus	S. texanus		A type of goblin shark
Asteracanthus	A. sp.		A hybodontid shark
Brachyrhizodus	B. wichitaensis B. mcnultyi		A prehistoric stingray
Cretolamna	C. appendiculata		An otodontid Shark
Cretodus	Cretodus sp.		A cretoxyrhinid shark
Carcharias	Carcharias sp.		A genus of sand shark (sand tiger sharks)
Odontaspis	Odontaspis sp.		A type of sand shark

Ray-finned fish

Based on the Paleobiology Database & Stringer et al (2018). Some species are known only from otolith remains from Blue Banks & Auger Hole Landings, North Carolina, which are indicated:^[8][9]

Genus	Species	Location	Material	Notes	Images
Albula	?A. campaniana	Blue Banks & Auger Hole Landings, NC	263-378 otoliths	A bonefish.
	?A. cf. A. ripleyensis	Blue Banks Landing, NC	1 otolith
	A. sp.	Phoebus Landing, NC
Anomoeodus	A. phaseolus	Phoebus Landing, NC		A pycnodontid pycnodont.
Ariidae indet.		Blue Banks Landing, NC	11 otoliths	A sea catfish of uncertain affinities.
Aulopidae indet.		Blue Banks Landing, NC	1 otolith	A flagfin of uncertain affinities.
Beryx	?B. maastrichtiensis	Blue Banks & Auger Hole Landings, NC	55 otoliths	A potential relative of alfonsinos.
	?B. zideki		41 otoliths
?Congridae indet.		Auger Hole Landing, NC	1 otolith	An apparent conger eel of uncertain affinities.
Cylindracanthus	C. ornatus	Phoebus Landing, NC		A fish of uncertain affinities.
Enchodus	E. cf. petrosus	Phoebus Landing, NC		An enchodontid aulopiform.
Gonostomatidae indet.		Blue Banks & Auger Hole Landings, NC	4 otoliths	A bristlemouth of uncertain affinities.
Hoplostethus	?H. coffeesandensis	Blue Banks & Auger Hole Landings, NC	4 otoliths	A slimehead.
Kokenichthys	K. ensis	Blue Banks Landing, NC	2 otoliths	An elopiform or osteoglossiform.[10]
Lepisosteidae indet.		Phoebus Landing, NC		A gar.
Megalopidae indet.		Blue Banks Landing, NC	1 otolith	A tarpon of uncertain affinities.
Osmeroides	O. weileri	Blue Banks Landing, NC	6 otoliths	An osmeroidid elopomorph.
Paralbula	P. casei	Phoebus Landing, NC		A phyllodontid elopomorph.
?Pempheris	?P. huddlestoni	Auger Hole Landing, NC	1 otolith	An apparent sweeper.
Percoidei indet.		Blue Banks & Auger Hole Landings, NC	5 otoliths	A percoid.
?Polymixia	?P. cf. harderi	Blue Banks Landing, NC		An apparent beardfish.
Pterothrissus	P. carolinensis	Blue Banks Landing, NC	67 otoliths	A pterothrissine bonefish.
Saurodon	S. sp.	Phoebus Landing, NC		A saurodontid ichthyodectiform.
Stephanodus	S. sp.	Phoebus Landing, NC		A pycnodont.
Xiphactinus	X. audax	Phoebus Landing, North Carolina, NC		An ichthyodectid ichthyodectiform.
	X. vetus

Reptiles

Records from SC based on Schwimmer et al (2015):^[6]

Dinosaurs

Ornithischians

Based mainly on Brownstein (2018):^[4]

Ornithischians of the Tar Heel/Coachman Formation
Genus	Species	Location	Notes	Images
cf. Hadrosaurus	?H. foulkii	Phoebus Landing & Sampson County, NC[11]	A hadrosaurid, tentatively assigned to the well-known H. foulkii.
"Hadrosaurus"	"H." minor	Phoebus Landing, NC	A small or juvenile hadrosaur, nomen dubium.
Hypsibema	H. crassicauda	Phoebus Landing & Sampson County, NC	A gigantic hadrosauroid. First discovered in North Carolina from Sampson County, 1869, and described by Edward Drinker Cope. It was measured to be 12-17 meters, making it one of the largest hadrosauroids. Type locality for genus and species.
Leptoceratopsidae indet.		Sampson County, NC	A leptoceratopsid ceratopsian. Known from an indeterminate left maxilla found in 2016.[12]
Lophorhothon	L. atopus	Phoebus Landing, NC	A hadrosauromorph. Originally described from the Mooreville Chalk Formation, Alabama.

An indeterminate hadrosauroid is known from Stokes Quarry, SC.^[4]

Theropods

Theropods of the Tar Heel/Coachman Formation
Genus	Species	Location	Notes	Images
Appalachiosaurus	A. montgomeriensis	Stokes Quarry, SC	A large eutyrannosaur.[4]
cf. Coelosaurus (="Ornithomimus")	C. sp.	Phoebus Landing, NC	An intermediate ornithomimosaur.[4][13]
Dromaeosauridae indet.		Sampson County, NC	A large dromaeosaurid, larger than Saurornitholestes but smaller than Dakotaraptor.[14]
Dryptosaurus	D. aquilunguis	Phoebus Landing, NC	A large dryptosaurid eutyrannosaur. Originally known from the Maastrichtian of New Jersey, but similar remains referable to this species have been recovered from the Tar Heel.[4]
Saurornitholestes	S. langstoni	Burches Ferry & Stokes Quarry, SC	A widespread dromaeosaurid ("raptor"). Specimens from this formation provided the first evidence of this species from Appalachia.[4][15][16]

Indeterminate theropods, ornithomimosaurs, and maniraptorans are known from Stokes Quarry.^[4]

Crocodylomorphs

Based on the Paleobiology Database:^[8]

Genus	Species	Location	Notes	Images
Borealosuchus	B. formidabilis	Phoebus Landing, NC	A eusuchian.
Bottosaurus	B. sp.	Stokes Quarry, SC	An early caiman.
Deinosuchus	D. rugosus (=Thecachampsa rugosa, Polydectes biturgidus, Polyptychodon rugosus)	Phoebus Landing & Clifton Farm, NC Stokes Quarry, SC	An alligatoroid, one of the largest known crocodilians. Type locality for genus and species.
Gavialoidea indet.		Stokes Quarry, SC	A gavialoid.

Turtles

Based on the Paleobiology Database:^[8]

Genus	Species	Location	Notes	Images
Adocus	A. beatus	Phoebus Landing, NC Stokes Quarry, SC	An adocid.
Bothremys	B. cooki	Phoebus Landing, NC	A bothremydid side-necked turtle.
Chedighaii	C. barberi	Phoebus Landing, NC	A bothremydid side-necked turtle.
	C. hutchinsoni
Corsochelys	C. bentlyi	Stokes Quarry, SC	A sea turtle, likely a dermochelyid. Type locality for species.
Euclastes	E. wielandi	Stokes Quarry, SC	A pancheloniid sea turtle.
Osteopygis	O. emarginatus	Phoebus Landing, NC	A macrobaenid.
?Taphrosphys	?T. dares	Phoebus Landing, NC	A bothremydid side-necked turtle, taxonomic placement disputed.
Toxochelys	T. sp.	Stokes Quarry, SC	A toxochelyid sea turtle.
"Trionyx"	"T." halophilus	Phoebus Landing, NC	A stem-softshell turtle, likely not an actual member of the genus Trionyx. Species names are nomina dubia.
	"T." priscus	Stokes Quarry, SC

Plesiosaurs

Genus	Species	Location	Notes	Images
Elasmosauridae indet.		Stokes Quarry, South Carolina	An elasmosaurid.

Squamates

Genus	Species	Location	Notes	Images
Halisaurus	H. sp.	Phoebus Landing, NC	A halisaurine mosasaur.
Platecarpus	P. sp.	Phoebus Landing, NC	A plioplatecarpine mosasaur.
Prognathodon	P. sp.	Phoebus Landing, NC	A mosasaurine mosasaur.
Teiidae indet.		Stokes Quarry, SC	A teiid lizard.
Tylosaurus	T. sp.	Phoebus Landing, NC Stokes Quarry, SC	A tylosaurine mosasaur.

Mammals

Based on the Paleobiology Database:^[17]

Genus	Species	Location	Notes	Images
Marsupialia indet.		Darlington County, SC	A presumed marsupial relative.[17]
Multituberculata indet.		Darlington County, SC	A multituberculate.[17]

References

1. Longrich, Nicholas R. (2016). "A ceratopsian dinosaur from the Late Cretaceous of eastern North America, and implications for dinosaur biogeography". Cretaceous Research. 57: 199–207. Bibcode:2016CrRes..57..199L. doi:10.1016/j.cretres.2015.08.004.
2. "Geolex — TarHeel publications". ngmdb.usgs.gov. Retrieved 2024-11-13.
3. Mitra, Madhumi (2002-07-29). Paleopalynology of the Tar Heel Formation of Atlantic Coastal Plain of North Carolina, United States (Thesis).
4. 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.
5. "PBDB Collection". paleobiodb.org. Retrieved 2024-11-13.
6. 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.
7. Schwimmer, David R.; Weems, Robert E.; Sanders, Albert E. (2015). "A Late Cretaceous Shark Coprolite with Baby Freshwater Turtle Vertebrae Inclusions". PALAIOS. 30 (9/10): 707–713. ISSN 0883-1351.
8. Czaplewski, John J. "PBDB Navigator". paleobiodb.org. Retrieved 2024-10-10.
9. Stringer, Gary L.; Clements, Don; Sadorf, Eric; Shannon, Kevin (2019). "First Description and Significance of Cretaceous Teleostean Otoliths (Tar Heel Formation, Campanian) from North Carolina". Eastern Paleontologist. 4: 1–22. ISSN 2475-5117.
10. Stringer, Gary L.; Sloan, James Carson (2023-05-25). "First Cretaceous teleostean otolith assemblage (Arkadelphia Formation, upper Maastrichtian) from Arkansas, USA, early Gadiformes, and the Western Interior Seaway". PaleoBios. 40 (3). doi:10.5070/P940361192. ISSN 2373-8189.
11. NCSM Paleontology Database
12. Longrich, Nicholas R. (2016-01-01). "A ceratopsian dinosaur from the Late Cretaceous of eastern North America, and implications for dinosaur biogeography". Cretaceous Research. 57: 199–207. doi:10.1016/j.cretres.2015.08.004. ISSN 0195-6671.
13. Baird D., and Horner, J., 1979, "Cretaceous dinosaurs of North Carolina" Brimleyana 2: 1–28
14. Brownstein, Chase D. (2018-12-01). "A large dromaeosaurid from North Carolina". Cretaceous Research. 92: 1–7. Bibcode:2018CrRes..92....1B. doi:10.1016/j.cretres.2018.07.006. ISSN 0195-6671. S2CID 135459468.
15. Brownstein, Chase D. (2018-04-05). "Diversity of raptor dinosaurs in southeastern North America revealed by the first definite record from North Carolina". PeerJ Preprints. doi:10.7287/peerj.preprints.26829v1.
16. Brownstein, Chase D. (2018). "The distinctive theropod assemblage of the Ellisdale site of New Jersey and its implications for North American dinosaur ecology and evolution during the Cretaceous". Journal of Paleontology. 92 (6): 1115–1129. Bibcode:2018JPal...92.1115B. doi:10.1017/jpa.2018.42. ISSN 0022-3360.
17. "PBDB Collection". paleobiodb.org. Retrieved 2024-11-15.