Antlers Formation

Antlers Formation
Stratigraphic range: Early Cretaceous
Type	Geological formation
Location
Region	North America

The Antlers Formation occurs as a band of strata from Arkansas through southern Oklahoma into northeastern Texas. It consists of 150 m (490 ft) of silty to sandy mudstones, fine- to coarse grained sandstones that are poorly to moderately sorted and cemented with clay or calcium carbonate. In places the sandstone may be conglomeratic or ferruginous (rich in iron oxides).

Based on correlation with the Trinity Group of Texas, the Antlers Formation is estimated to be late Aptian-early Albian. This age range is supported by the presence of two dinosaurs that are also known from the Cloverly Formation, Deinonychus and Tenontosaurus.

Amphibians

Indeterminate frog remains. Possible indeterminate salamander remains.

Amphibians of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Albanerpeton	Albanerpeton arthridion					Albanerpeton

Basal vertebrates ("Fish")

References: Cifelli et al. 1999; Wedel et al. 2000, Kielan-Jarorowska and Cifelli 2001; Nydam and Cifelli 2002.

Cartilaginous fish

Chondrichthyans of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Hybodus	Hybodus buderi				Hybodontidae	Placeholder
	?Hybodus sp.
Lissodus	Lissodus anitae				Polyacrodontidae

Ray-finned fish

Possible indeterminate amiid remains. Possible indeterminate lepisosteid remains. Possible indeterminate semionotidae remains.

Actinopterygians of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes
Gyronchus	Gyronchus dumblei
?Palaeobalistum	?Palaeobalistum sp.

Mammals

Possible indeterminate deltatheroidan material. Indeterminate multituberculate remains. Indeterminate tribosphenidan remains.

Mammals of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes
Astroconodon	Astroconodon sp.
Atokatherium	Atokatherium boreni
?Paracimexomys	Paracimexomys crossi

Reptiles

Crurotarsans

Possible indeterminate atoposaurid remains. Possible indeterminate goniopholidid remains. Possible indeterminate pholidosaurid remains.

Crurotarsans of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes
Bernissartia	Bemissartia sp.

Lepidosaurs

Possible indetrminate scincid remains.

Lepidosaurs of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes
Atokasaurus	Atokasaurus metarsiodon
Bemissartia	Bemissartia sp.
Ptilotodon	Ptilotodon wilsoni

Ornithischians

Ornithischians of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Tenontosaurus	Tenontosaurus sp.					Tenontosaurus

Saurischians

Possible indeterminate bird remains are known from the formation.

Saurischians of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Acrocanthosaurus	Acrocanthosaurus atokensis					Sauroposeidon
Astrodon	Astrodon sp.
Deinonychus	Deinonychus sp.
Sauroposeidon	Sauroposeidon proteles			"[Four] cervical vertebrae."

Turtles

Turtles of the Antlers Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes
?Glyptops	Glyptops sp.
Naomichelys	Naomichelys sp.

See also

• List of dinosaur-bearing rock formations

Further reading

• Cifelli, R. Gardner, J.D., Nydam, R.L., and Brinkman, D.L. 1999. Additions to the vertebrate fauna of the Antlers Formation (Lower Cretaceous), southeastern Oklahoma. Oklahoma Geology Notes 57:124-131.
• Nydam, R.L. and R. L. Cifelli. 2002a. Lizards from the Lower Cretaceous

(Aptian-Albian) Antlers and Cloverly formations. Journal of Vertebrate Paleontology. 22:286–298.

• Kielan-Jarorowska, Z., and Cifelli, R.L. 2001. Primitive boreosphenidan mammal (?Deltatheroida) from the Early Cretaceous of Oklahoma. Acta Palaeontologica Polonica 46: 377-391.
• Wedel, M.J., Cifelli, R.L., and Sanders, R. K. 2000. Sauroposeidon Proteles, A new sauropod from the Early Cretaceous of Oklahoma. Journal of Vertebrate Paleontology 20:109-114.