The Tuscahoma Formation or Tuscahoma Sand is a geologic formation in Mississippi and Alabama, USA. It preserves fossils dating back to the early Paleogene period, from the Late Paleocene and Early Eocene.[1] It was primarily deposited in a marine habitat, but one Wasatchian-aged locality near Meridian, Mississippi was deposited in an estuarine habitat that preserves a significant terrestrial vertebrate fauna, known as the "Red Hot local fauna".[2][3] It preserves one of the most diverse early Eocene mammalian faunas from eastern North America, roughly contemporaneous with the Willwood Formation of Wyoming.[3][4]

Tuscahoma Formation
Stratigraphic range: Thanetian to earliest Ypresian, 57–55 Ma
TypeFormation
Unit ofWilcox Group
Sub-unitsBells Landing Member, Greggs Landing Member
UnderliesBashi Formation
OverliesNanafalia Formation
Lithology
PrimarySandstone
Location
RegionMississippi, Alabama
Country United States

Vertebrate paleofauna

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Ray-finned fishes

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Based on the Paleobiology Database:[5]

Ray-finned fishes of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Albula A. eppsi Lauderdale County, Mississippi Early Eocene A bonefish.  
A. oweni
Brychaetus B. muelleri A bonytongue.  
Egertonia E. isodonta A phyllodontid.
Lepisosteus L. sp. A gar. Assigned to the European species L. suessionensis (itself a junior synonym of L. fimbriatus), but this is unlikely due to their differring ranges.[6]  
Palaeocybium P. proosti A mackerel.
Phyllodus P. toliapicus A phyllodontid.  
Pycnodus P. bowerbanki A pycnodont.  
Trichiurides T. sagittidens A cutlassfish.

Reptiles

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Based on the Paleobiology Database:[4][7]

Reptiles of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Palaeophis P. casei Meridian, Mississippi Early Eocene A marine palaeophiid snake.  
P. littoralis
P. virginianus
Tuscahomaophis T. leggetti Late Paleocene An alethinophidian snake.

Mammals

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The Tuscahoma Formation preserves a diversity of earliest Eocene-aged mammals. Almost all mammals are known only from isolated teeth. There appear to be significant differences in the faunal composition between the Tuscahoma Formation and the contemporaneous Bighorn Basin of the western US, indicating some level of provincialism in North American mammal species assemblages of the time. The formation appears to have been biased against the preservation of large-sized mammals, meaning that the majority of mammal remains from the formation are of smaller taxa.[3]

Based on the Paleobiology Database and Dawson & Beard (2009):[4][3]

Metatheria

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Metatherians of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Mimoperadectes M. sowasheensis Meridian, Mississippi Early Eocene A peradectid.  
Peratherium P. mcgrewi A herpetotheriid.  

Cimolesta

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Cimolestans of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Coryphodon C. sp. Meridian, Mississippi Early Eocene A pantodont.  
Naranius N. americanus A cimolestid. Type locality of species.
Palaeosinopa P. aestuarium A pantolestid. Type locality of species.  

Macroscelidea

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Macroscelideans of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Haplomylus H. meridionalis Meridian, Mississippi Early Eocene An apheliscid.

Ungulates

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Ungulates of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Diacodexis D. sp. Meridian, Mississippi Early Eocene An even-toed ungulate.  
Ectocion E. nanabeensis A phenacodont. Type locality of species.  
Hyracotherium H. sp. An odd-toed ungulate.  

Pan-Carnivorans

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Ungulates of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Eogale E. parydros Meridian, Mississippi Early Eocene A miacid carnivoramorph. Type locality of genus and species.
Gracilocyon G. igniculus A carnivoraform.  
"Miacis" "M." sp. A carnivoramorph.
Prototomus P. sp. A sinopid hyaenodont.  
Uintacyon U. sp. A carnivoraform.  
Vassacyon V. sp. A carnivoraform.  
Viverravus V. laytoni A viverravid carnivoramorph.  
Viverriscus V. omnivorus A viverravid carnivoramorph. Type locality of genus and species.

Eulipotyphlans

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Eulipotyphlans of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Colpocherus C. mississippiensis A sespedectid. Type locality of genus and species.
Diacocherus D. dockeryi An erinaceoid. Type localiy of species.
Plagioctenodon P. dormaalensis A nyctitheriid.
Talpavoides T. dartoni A stem-erinaceid.[8]
Wyonycteris W. primitivus A nyctitheriid. Type locality of species.  

Apatotherians

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Apatotherians of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Apatemys A. pygmaeus Meridian, Mississippi Early Eocene An apatemyid. Type locality of species.  

Rodents

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Rodents of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Corbarimys C. nomadus Meridian, Mississippi Early Eocene An ischyromyoid.[9]
Franimys F. actites An ischyromyid.
Paramys P. dispar An ischyromyid.  
Tuscahomys T. major A cylindrodontid. Type locality of genus and species.
T. medius
T. minor

Primates

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Primates of the Tuscahoma Formation
Genus Species Location Stratigraphic position Material Notes Images
Choctawius C. foxi Meridian, Mississippi An omomyid. Type locality of genus and species.
Teilhardina T. magnoliana An omomyid.  

See also

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References

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  1. ^ "Geolex — Tuscahoma publications". ngmdb.usgs.gov. Retrieved 2024-11-21.
  2. ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-11-21.
  3. ^ a b c d Beard, K. Christopher; Dawson, Mary R. (2009). "Early Wasatchian Mammals of the Red Hot Local Fauna, Uppermost Tuscahoma Formation, Lauderdale County, Mississippi". Annals of Carnegie Museum. 78 (3): 193–243. doi:10.2992/007.078.0301. ISSN 0097-4463.
  4. ^ a b c "PBDB Collection". paleobiodb.org. Retrieved 2024-12-10.
  5. ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-12-10.
  6. ^ Weems, Robert E. (1998). "Actinopterygian Fish Remains from the Paleocene of South Carolina". Transactions of the American Philosophical Society. 88 (4): 147–164. doi:10.2307/1006672. ISSN 0065-9746.
  7. ^ "PBDB Collection". paleobiodb.org. Retrieved 2024-12-10.
  8. ^ Vitek, Natasha S.; Morse, Paul E.; Boyer, Doug M.; Strait, Suzanne G.; Bloch, Jonathan I. (2021). "Evaluating the responses of three closely related small mammal lineages to climate change across the Paleocene–Eocene thermal maximum". Paleobiology. 47 (3): 464–486. doi:10.1017/pab.2021.12. ISSN 0094-8373.
  9. ^ Vianey-Liaud, Monique; Marivaux, Laurent (20 September 2021). "The beginning of the adaptive radiation of Theridomorpha (Rodentia) in Western Europe: morphological and phylogenetic analyses of early and middle Eocene taxa; implications for systematics". Palaeovertebrata. 44 (2): e2. doi:10.18563/pv.44.2.e2. ISSN 0031-0247. OCLC 9257882797. Retrieved 26 July 2024.