Triassic Microvertebrate Fossils from North Carolina

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com

In the new Journal of Paleontology:

Andrew B. Heckert, Jonathan S. Mitchell, Vincent P. Schneider, and
Paul E. Olsen (2012)
Diverse New Microvertebrate Assemblage from the Upper Triassic Cumnock
Formation, Sanford Subbasin, North Carolina, USA.
Journal of Paleontology 86(2): 368-390
doi: http://dx.doi.org/10.1666/11-098.1
http://www.bioone.org/doi/abs/10.1666/11-098.1



The Moncure microvertebrate locality in the Cumnock Formation, Sanford
sub-basin, North Carolina, dramatically increases the known Late
Triassic age vertebrate assemblage from the Deep River Basin. The
50,000 recovered microvertebrate fossils include osteichthyans,
amphibians, and numerous lepidosauromorph, archosauriform, and
synapsid amniotes. Actinopterygian fossils consist of thousands of
scales, teeth, skull, and lower jaw fragments, principally of
redfieldiids and semionotids. Non-tetrapod sarcopterygians include the
dipnoan Arganodus sp., the first record of lungfish in the Newark
Supergroup. Temnospondyls are comparatively rare but the preserved
centra, teeth, and skull fragments probably represent small (juvenile)
metoposaurids. Two fragmentary teeth are assigned to the unusual
reptile Colognathus obscurus (Case). Poorly preserved but intriguing
records include acrodont and pleurodont jaw fragments tentatively
assigned to lepidosaurs. Among the archosauriform teeth is a taxon
distinct from R. callenderi that we assign to Revueltosaurus olseni
new combination, a morphotype best assigned to cf. Galtonia, the first
Newark Supergroup record of Crosbysaurus sp., and several other
archosauriform tooth morphotypes, as well as grooved teeth assigned to
the recently named species Uatchitodon schneideri. Synapsids
represented by molariform teeth include both “traversodontids”
assigned to aff. Boreogomphodon and the “dromatheriid” Microconodon.
These records are biogeographically important, with many new records
for the Cumnock Formation and/or the Newark Supergroup. In particular,
Colognathus, Crosbysaurus, and Uatchitodon are known from basins of
Adamanian age in the southwestern U.S.A. These new records include
microvertebrate taxa more typical of non-Newark basins (abundant
archosauriforms, temnospondyls, lungfish) as well as more typical
Newark osteichthyans and synapsid-rich faunal elements.