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GSA talks about dinosaur-related stuff

From: Ben Creisler

A number of abstracts of talks at the GSA meeting about dinosaurs,
pterosaurs, parasites


Paper No. 183-12
Presentation Time: 9:00 AM-6:00 PM

HANKS, H. Douglas1, HAIRE, Scott A.2, and ERICKSON, Bruce R.1, (1)
Paleontology, Science Museum of Minnesota, 120 W. Kellogg Blvd, St.
Paul, MN 55102, hanks.douglas@gmail.com, (2) Biology, Science Museum
of Minnesota, 120 W. Kellogg Blvd, St. Paul, MN 55102
A new assemblage of Upper Cretaceous reptiles from the Campanian and
Maastrichtian deposits of eastern South Carolina contains numerous new
occurrences of theropod and hadrosaurid dinosaurs that increase the
number of localities producing dinosaur remains in the eastern United
States to over twenty-five. Dinosaur remains were found with many
incomplete bones of pleurodira (side-necked turtles), Bothremys, the
aquatic turtles Adocus, Agomphus , trionychids and sea turtles. Among
other abundant reptilian remains are four crocodilians (Deinosuchus,
Thoracosaurus, Bottosaurus and Borealosuchus), three mosasaur taxa,
(Mosasaurus, Platecarpus and Tylosaurus), elasmosaur plesiosaurs, and
a teiid lizard. This assemblage is a mixture of marine and non-marine
taxa dominated by turtles and crocodiles, consisting of fragmented
bones that are characteristic of lag deposits.

Fourteen localities were investigated to determine their geologic
history as well as the stratigraphic position of the fossils contained
in them. Evidence of dinosaurs was found at six of these localities,
which include two principal deposits, one at Stokes Quarry in
Darlington County (former Stokes Quarry) that is age equivalent to the
mid-Campanian Coachman Formation, and the other being the late
Campanian Donoho Creek Formation at Kingstree in Williamsburg County.
These two sites yielded the majority of the dinosaurian specimens. The
Kingstree site was collected by Erickson during the 1982/83 field
season, producing the earliest dinosaurian remains. These collections
are housed in the South Carolina State Museum (SCSM), Columbia, S.C.
and the Science Museum of Minnesota, St. Paul, MN. Other dinosaurian
material is housed in the Charleston Museum (CM), Charleston, S.C.

2012 GSA Annual Meeting in Charlotte
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2012 GSA Annual Meeting in Charlotte
Paper No. 259-7
Presentation Time: 3:00 PM-3:15 PM

ENGELMANN, George F.1, CHURE, Daniel J.2, BRITT, Brooks B.3, and
ANDRUS, Austin3, (1) Department of Geography & Geology, University of
Nebraska - Omaha, 60th And Dodge St, Omaha, NE 68182,
gengelmann@unomaha.edu, (2) Dinosaur National Monument, National Park
Service, Box 128, Jensen, UT 84035, (3) Geological Sciences, Brigham
Young University, S-389 ESC, Provo, UT 84602
The Saints and Sinners Quarry, in the Nugget Sandstone near Dinosaur
National Monument in northeastern Utah, has yielded thousands of bones
of a new theropod dinosaur. This locality occurs in an interdunal
interval well within the dominantly eolian upper part of the Nugget
Ss. Recently, we have also recovered remains of small, non-dinosaurian
vertebrates, including a remarkable, articulated, partial skeleton
that is unmistakably identifiable as a drepanosaur. Drepanosaurs are a
small, enigmatic group of reptiles characterized by a number of
bizarre and highly distinctive features throughout the skeleton.

Drepanosaurs are geographically widespread across Europe, North
America, and Asia, but are temporally restricted to the Triassic (Late
Carnian through Late Norian), with the highest stratigraphic
occurrence in the Rock Point Member of the Chinle Fm. The new taxon is
stratigraphically higher than this, occurring about 55 meters above
the base of the eolian part of the Nugget Ss. This represents a range
extension for the Drepanosauromorpha, but whether that extension is
still higher in the uppermost Triassic or into the Lower Jurassic
cannot be determined without other evidence. The presence of the
ichnotaxon Brachychirotherium in the basal beds of the Nugget in the
study area and elsewhere has been interpreted as indicating a Triassic
age for at least the lower part of the Nugget. The upper, eolian beds
of the Nugget Sandstone have been considered to be part of the Lower
Jurassic, although there is no strong evidence for this, but the
presence of drepanosaurs in the Saints and Sinners Quarry suggests
that at least the lower part of the eolian beds could be Triassic.

The presence of drepanosaurs in an interdunal facies within the eolian
depositional environment of the Nugget also presents a paleoecological
problem. Previously described drepanosaur taxa do not occur within
eolian depositional environments, and morphologic characteristics of
the animals have been interpreted as indicative of arboreal habitat.
Possible explanations for these apparent inconsistencies may be that
drepanosaurs were more diverse taxonomically and ecologically than the
record indicates, or that the principal adaptations of the group were
correlated with common aspects of environments that appear strikingly
dissimilar to us.

2012 GSA Annual Meeting in Charlotte
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2012 GSA Annual Meeting in Charlotte
Paper No. 89-28
Presentation Time: 9:00 AM-6:00 PM

GORSCAK, Eric1, O'CONNOR, Patrick M.2, STEVENS, Nancy J.2, and
ROBERTS, Eric M.3, (1) Biological Sciences, Ohio University, Athens,
OH 45701, eric.gorscak@gmail.com, (2) Department of Biomedical
Sciences, Ohio University, Athens, OH 45701, (3) Earth and
Environmental Sciences, James Cook University, PO Box 6811, Cairns,
Qld, 4870, Australia
Sauropods were one of the most successful dinosaur clades with notable
peaks in diversity in the Late Jurassic and Late Cretaceous.
Titanosaurians represent the most speciose and diverse clade of
Cretaceous sauropods, reaching a global distribution by the end of the
Cretaceous. Despite this widespread occurrence, titanosaurians are
rare components of Cretaceous African faunas. Two representatives are
currently recognized, Malawisaurus from the Lower Cretaceous Dinosaur
Beds (DB) of Malawi and Paralititan from Upper Cretaceous deposits
near Bahariya Oasis, Egypt. Recent expeditions to the middle
Cretaceous Galula Formation of the Rukwa Rift Basin (RRB) in southwest
Tanzania have aided in expanding our knowledge into the Cretaceous
titanosaurian diversity of Africa. Critical titanosaurian fossils
recovered include a semi-articulated individual (RRBP 07409), isolated
yet morphologically variable teeth, and several isolated,
well-preserved limb elements (e.g., humeri) that express morphology
consistent with titanosauriformes. Recovered elements of RRBP 07409
include components of the postcranial axial (cervical and caudal
vertebrae, ribs) and appendicular (scapula, humerus, ulna, ilium, and
pubis) skeletons. Both parsimony and bayesian phylogenetic analyses
were conducted to assess the relationship of RRBP 07409 and is placed
as the sister taxon to the clade consisting of Malawisaurus and
‘derived’ titanosaurians. RRBP 07409 differs from Malawisaurus in
gross morphology of the caudal vertebrae and more robust humerus.
Additionally, tooth morphotypes vary with regard to combinations of
cross-sectional shape (cylindrical, elliptical, or D-shaped),
slenderness (wide or thin), and number of wear facets (unworn, one,
two, or three). At present, there are several slender teeth with high
angled wear facets that is consistent with titanosaurians. However,
other morphotypes are not readily assignable to any specific clade and
need further comparative work. Ongoing comparative work on materials
collected from the RRB and the DB of Malawi is necessary for
differentiating these potentially contemporaneous faunas. A detailed
survey and characterization of these assemblages is essential for
developing paleobiogeographic comparisons with other sub-equatorial
Cretaceous faunas.

2012 GSA Annual Meeting in Charlotte
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2012 GSA Annual Meeting in Charlotte
Paper No. 151-4
Presentation Time: 9:00 AM-9:15 AM

HUANG, Diying, Nanjing Institute of Geology and Palaeontology, CAS,
No. 39 East Beijing Road, Nanjing 210008 China, huangdiying@sina.com
Newly discovered Mesozoic fleas have been recently reported from the
Middle Jurassic Daohugou fauna (ca. 165 Ma) and the Early Cretaceous
Jehol fauna (ca. 125 Ma) of Northeast China. These giant fleas are
represented by three forms each with both with males and females. The
females are slightly to distinctly larger than the males. These
ancient ectoparasites display some general habitus, such as large size
(more than 2 cm long in some specimens), more or less dorso-ventrally
flattened body, and non-jumping hind legs. Their developed,
posteriorly-directed setae on thorax and abdomen and scattered
ctenidia on legs indicate an ectoparasitical behavior that lived on
haired or feathered vertebrates. Most modern fleas parasitize mammals,
and small, advanced groups (about 5%) parasitize birds. The possible
Mesozoic hosts of these fossil fleas include dinosaurs and pterosaurs
with hair-like feathers, early birds, and early mammals. This primary
study indicates clear morphological differences between these Mesozoic
fleas. At least three different groups may be distinguished. These
are: 1) the Middle Jurassic types (Middle Jurassic to Early
Cretaceous, China), armed with a typical long and serrate
piercing-suctorial siphon like some Recent groups (e.g. Tungidae); 2)
Tarwinia-type (Early Cretaceous, China and Australia), armed with a
relatively simple siphon and different tarsal structures; 3)
Saurophthirus-type (Early Cretaceous, Russia and China), armed with a
relatively simple siphon and very slender and elongate legs. The basal
morphological differences probably indicate a remarkable adaptability
to different hosts.

Strashila is the most bizarre animal among all known fossil insects.
It was hypothesized to be an ectoparasite, even a supposed dinosaur
parasite. The new morphological details indicate it is a true aquatic
insect. Moreover, Saurodectes vrsanskyi from Siberia was suggested to
have louse affinities, but it is more likely a wingless dipteran.

2012 GSA Annual Meeting in Charlotte
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2012 GSA Annual Meeting in Charlotte
Paper No. 158-29
Presentation Time: 9:00 AM-6:00 PM

MCLAIN, Matthew Aaron, 6 Perigo Pass, North Creek, NY 12853,
Pterosaurs were flying archosaurs whose fossils have been found on
every continent. These fossils first appear in rocks of the Late
Triassic, and they cease to appear at the Cretaceous-Paleogene
boundary. The currently unpublished pterosaur database PteroTerra
records the paleoenvironments and families for over 500 specimens. 463
specimens had listed paleoenvironments and were utilized for this
study. These paleoenvrionments were tallied and compared for six
portions of the Mesozoic: the Late Triassic, Early Jurassic, Middle
Jurassic, Late Jurassic, Early Cretaceous, and Late Cretaceous. Then,
pterosaur families were listed for each geologic epoch. The results of
these comparisons seem to show a change from pterosaurs in marine
paleoenvironments in the Early Jurassic and Middle Jurassic, to a
great diversity of paleoenvironments in the Late Jurassic and Early
Cretaceous. Simultaneously, the number of families present almost
doubles from the Middle Jurassic to Late Jurassic, and then continues
to increase into the Early Cretaceous. Thus, it appears that
increasing morphological diversity in pterosaurs parallels increasing
habitat diversity.

2012 GSA Annual Meeting in Charlotte
General Information for this Meeting