Tomahawk locality, USNM 39981: Carnian, Virginia
collected by Olsen, Sues 1983, 1988-1992

List of taxa
Where & when
Taphonomy & methods
Metadata & references
Taxonomic list
Dictyopygae sp.
? Lissamphibia indet.
Gardner and DeMar 2013
Gastropoda indet. Cuvier 1797
Chondrichthyes - Hybodontiformes
Lissodus sp. Brough 1935
Reptilia - Procolophonidae
Gomphiosauridion baileyae n. gen., n. sp. Sues and Olsen 1993
Sues and Olsen 1993 1 specimen
USNM 448630, partial maxilla
Xenodiphyodon petraios n. gen., n. sp. Sues and Olsen 1993
Sues and Olsen 1993 1 specimen
USNM 448631, partial dentary
Uatchitodon kroehleri n. gen., n. sp. Sues 1991
12 specimens
USNM 448611 (holotype). USNM 448603-448, 610, 448621-448622, 448624, teeth
Parasuchia indet. Huxley
synonym of Phytosauria
Isolated teeth
Archosauria indet. Cope 1869
Sues and Olsen 1990 10 specimens
USNM 448587, associated osteoderms (holotype). USNM 448580-448586, 448588, 448589
    = Euscolosuchus olseni n. gen., n. sp. Sues 1992
Sues 1992
Lepidosauria indet. (Haeckel 1866)
Reptilia - Rhynchocephalia
Sphenodontia indet. (Jaekel 1910)
Sues and Olsen 1990 1 specimen
"similar to Diphydontosaurus"
Microconodon tenuirostris Osborn 1886
Sues and Olsen 1990 6 specimens
USNM 437637, ROM 44300, 44301, partial dentaries, USNM 448579, 448600, ROM 44302, isolated teeth
Boreogomphodon jeffersoni n. gen., n. sp. Sues and Olsen 1990
Sues and Olsen 1990 41 specimens
USNM 437632, left maxilla (holotype). CM 20050, 76800, 76801, 78803, USNM 437634, 437635, 437636, 448562, 448570, 448593, 448599, 448632, 448633, VMNH 3575, 3578, cranial remains. CM 76805, 76807, 76808, 76812, 76815, 76818, USNM 448563-448569, 448571-448573, 448575, 448576, 448578, 448597, 448601, 448625, 448629, isolated teeth. USNM 448602, 448598, VMNH 3577, postcranial elements
Pteridophyta indet. Haeckel 1875
see common names

Country:United States State/province:Virginia County:Chesterfield
Coordinates: 37.5° North, 77.7° West (view map)
Paleocoordinates:2.4° North, 16.1° West
Basis of coordinate:stated in text
Altitude:91 meters
Geographic resolution:outcrop
Period:Triassic Epoch:Late/Upper Triassic
Stage:Carnian 10 m.y. bin:Triassic 3
Key time interval:Carnian
Age range of interval:237.00000 - 228.00000 m.y. ago
Geological group:Newark Formation:Vinita Member:Tomahawk Creek
Stratigraphic resolution:bed
Stratigraphy comments: "Based on conchostracans, Kozur & Weems (2007) recently dated much of the succession in the Richmond Basin and correlative units in the adjacent Taylorsville basin as early Carnian (Cordevolian), but earlier Huber et al. (1993) had argued for a late Carnian age of these strata. At the present time this controversy cannot be resolved" (Sues & Hopson 2010)
"Turkey Branch Formation" was previously used for this locality; Richmond Basin, Newark Supergroup
Lithology and environment
Primary lithology: silty,calcareous mudstone
Includes fossils?Y
Lithology description: "massive calcareous mudstone, together with small (1-10 mm) carbonate nodules, poorly preserved root traces...At least two irregular layers of fissile, more silty mudstone extend within the massive mudstone"
Environment:lacustrine - small
Geology comments: "shallow-wayer lacustrine origin"
Modes of preservation:body
Degree of concentration:concentrated
Size of fossils:macrofossils,mesofossils,microfossils
Spatial orientation:random
Preservation of anatomical detail:excellent
Articulated whole bodies:none
Associated major elements:none
Disassociated major elements:many
Disassociated minor elements:many
Collection methods and comments
Collection methods:bulk,surface (float),surface (in situ),chemical,mechanical,sieve,field collection
Reason for describing collection:general faunal/floral analysis
Museum repositories:USNM
Collectors:Olsen, Sues Collection dates:1983, 1988-1992
Also known as:1988-1
Database number:39159
Authorizer:M. Carrano, P. Holroyd Enterer:M. Carrano, P. Holroyd
Modifier:M. Carrano Research group:vertebrate
Created:2004-05-21 16:00:08 Last modified:2015-02-23 10:22:41
Access level:the public Released:2004-05-21 16:00:08
Creative Commons license:CC BY
Reference information

Primary reference:

10573.ETE H.-D. Sues, P. E. Olsen, and P. A. Kroehler. 1994. Small tetrapods from the Upper Triassic of the Richmond basin (Newark Supergroup), Virginia. In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods, N. C. Fraser and H.-D. Sues (eds.), Cambridge University Press 161-170 [M. Carrano/M. Carrano/M. Carrano]

Secondary references:

65027 J. D. Gardner and D. E. DeMar. 2013. Mesozoic and Palaeocene lissamphibian assemblages of North America: a comprehensive review. Palaeobiodiversity and Palaeoenvironments 93:459-515 [P. Holroyd/P. Holroyd/P. Holroyd]
34225 J. S. Mitchell, A. B. Heckert, and H.-D. Sues. 2010. Grooves to tubes: evolution of the venom delivery system in a Late Triassic reptile. Naturwissenschaften 97:1117-1121 [R. Butler/R. Butler/R. Butler]
7923 H.-D. Sues and P. E. Olsen. 1993. A new procolophonid and a new tetrapod of uncertain, possibly procolophonian affinities from the Upper Triassic of Virginia. Journal of Vertebrate Paleontology 13(3):282-286 [M. Uhen/M. Uhen/M. Uhen]
10658ETE H.-D. Sues. 1991. Venom-conducting teeth in a Triassic reptile. Nature 351:141-143 [M. Carrano/M. Carrano/M. Carrano]
34179 H.-D. Sues. 1992. A remarkable new armored archosaur from the Upper Triassic of Virginia. Journal of Vertebrate Paleontology 12:142-149 [R. Butler/R. Butler]
34178 H.-D. Sues. 2001. On Microconodon, a Late Triassic cynodont from the Newark Supergroup of eastern North America. Bulletin of the Museum of Comparative Zoology 156:37-48 [R. Butler/R. Butler]
34177 H.-D. Sues and J. A. Hopson. 2010. Anatomy and phylogenetic relationships of Boreogomphodon jeffersoni (Cynodontia: Gomphodontia) from the Upper Triassic of Virginia. Journal of Vertebrate Paleontology 30(4):1202-1220 [R. Butler/R. Butler]
10574ETE H.-D. Sues and P. E. Olsen. 1990. Triassic vertebrates of Gondwanan aspect from the Richmond Basin of Virginia. Science 249:1020-1023 [M. Carrano/M. Carrano/M. Carrano]