The Neverending New Papers III

["Jerry D. Harris" <jharris@dixie.edu>]

Hi All! -

     The papers in the _Arquivos do Museu Nacional, Rio do Janeiro_ that I
mentioned t'other day (as well as many other cool things) are available free
on-line at http://www.proyectodino.com.ar/ (click on "Produccion Cientifica"
in the left-hand menu).  Also there that I haven't mentioned are:

 

Porfiri, J.D., dos Santos, D., and Calvo, J.O. 2008. New information on
Megaraptor namunhuaiquii (Theropoda: Tetanurae), Patagonia: considerations
on paleoecological aspects. Arquivos do Museu Nacional, Rio de Janeiro
65(4):545-550.

ABSTRACT: Megaraptor is a giant theropod included as a possible
Coelurosauria. Its big claw was originally assigned to the digit II of the
pes. In the last year, the discovery of complete manus bones of a Megaraptor
allowed the knowledge of new morphological characters and, therefore, new
interpretations on phylogenetic relationships. As a result, Megaraptor was
proposed to be a basal tetanuran sharing characteristics with
charcarodontosaurids and spinosaurids. In general, manus of basal tetanurans
are quite unknown as they commonly lack phalanges, carpals or even the
complete manus, being the information on them limited. So that, the hand
elements of Megaraptor here studied represents an important material not
only for furnishing new morphological data but also for the understanding of
its behavior.



Fiorelli, L.E., and Calvo, J.O. 2008. The first 'protosuchian' (Archosauria:
Crocodyliformes) from the Cretaceous (Santonian) of Gondwana. Arquivos do
Museu Nacional, Rio de Janeiro 65(4):417-459.

ABSTRACT: The remains of ?protosuchians? from the Cretaceous come, to
exception of ?Las Hoyas crocodyliform? from the Lower Cretaceous of Spain,
exclusively of Central Asia: Zaraasuchus, Gobiosuchus, Zosuchus, and
Artzosuchus from the Upper Cretaceous of Mongolia; Tagarosuchus from Lower
Cretaceous of Southern Siberia; Edentosuchus, Sichuanosuchus, and
Shantungosuchus from Lower Cretaceous of China. We report a new basal
crocodyliform taxon, Neuquensuchus universitas gen.nov., sp.nov., from
Neuquén Province, Argentina, belonging to Bajo de la Carpa Formation,
representing the first and only ?protosuchian? from the Cretaceous of
Gondwana. The articulated and fragmentary materials belonged to a willowy,
slender species, with very long and thin extremities. As in Shantungosuchus,
the cervical centers are lengthened, with prominent ventral keel and well
developed anteroventral parapophyses. As in basal crocodylomorphs, it
possesses two sacral vertebrae. Also, a much enlarged scapular blade, with
well developed acromial ridge and the posterior edge similar to
Sichuanosuchus. The pronounced deltopectoral crest in the  complete humerus
is equivalent to Sichuanosuchus and as this, a circular, elongated and thin
shaft with the medial condyle longer than the lateral one. Also, the
complete ulna and radius is similar in their proportions to Sichuanosuchus.
As this, the pubis is lengthened, very thin in the half section and not very
expanded distally. The femur, tibia and fibula are elongated and similar to
other non-derivated crocodyliforms. Besides representing the first
Cretaceous ?protosuchian? of Gondwana, the occurrence of these outside of
Asia and Europe during the Cretaceous offers new evidence of pre-Albian
dispersion between Gondwana and Central Asia through Europe.




Some other nifty things:



Skutschas, P.P. 2008. A choristoderan reptile from the Lower Cretaceous of
Transbaikalia, Russia. Neues Jahrbuch für Geologie und Paläontologie
Abhandlungen 247(1):63-78.

ABSTRACT: New materials of the choristoderan reptile Khurendukhosaurus sp.
are described from the Early Cretaceous Murtoi Formation, Transbaikalia. The
Transbaikalian species is characterized by fused scapula and coracoid
(uncertain polarity character) and such advanced features as a
mediolaterally elongated marginal tooth bases, moderately laterally expanded
basal tubera on the basioccipital, clavicular facets on the interclavicle
that are continuous across the midline, closed vertebral notochordal canals
and the absence of the ventromedial crest on dorsal vertebrae. The
combination of derived states such as closed vertebral notochordal canals,
the presence of small spinous processes below the presacral
postzygapophyses, clavicular facets on the interclavicle that are continuous
across the midline and the absence of the ventromedial crest on dorsal
vertebrae, and primitive states such as closed neurocentral sutures;
anteroposteriorly elongated neural spines with transversally expanded and
rugose distal tips on dorsal vertebrae, elongated amphi- to platycoelus
vertebral centra, and pronounced ventral longitudinal keels on the cervical
vertebrae support the attribution of the Transbaikalian choristodere to
Khurendukhosaurus. Phylogenetic analysis places Khurendukhosaurus in a one
clade with the neochoristoderes, hyphalosaurids, Monjurosuchus and
Lazarussuchus. The basal position of Khurendukhosaurus is not confirmed, nor
is a referring of Khurendukhosaurus to the neochoristoderan family
Simoedosauridae.



Dudley, R., Byrnes, G., Yanoviak, S.P., Borell, B., Brown, R.M., and
McGuire, J.A. 2008. Gliding and the functional origins of flight:
biomechanical novelty or necessity? Annual Review of Ecology and Systematics
38:179-201. doi: 10.1146/annurev.ecolsys.37.091305.110014.

ABSTRACT: Abiomechanically parsimonious hypothesis for the evolution of
flapping flight in terrestrial vertebrates suggests progression within an
arboreal context from jumping to directed aerial descent, gliding with
control via appendicular motions, and ultimately to powered flight. The more
than 30 phylogenetically independent lineages of arboreal vertebrate gliders
lend strong indirect support to the ecological feasibility of such a
trajectory. Insect flight evolution likely followed a similar sequence, but
is unresolved paleontologically. Recently described falling behaviors in
arboreal ants provide the first evidence demonstrating the biomechanical
capacity for directed aerial descent in the complete absence of wings.
Intentional control of body trajectories as animals fall from heights (and
usually from vegetation) likely characterizes many more taxa than is
currently recognized. Understanding the sensory and biomechanical mechanisms
used by extant gliding animals to control and orient their descent is
central to deciphering pathways involved in flight evolution.




Khalifa, M.A., and Catuneanu, O. 2008. Sedimentology of the fluvial and
fluvio-marine facies of the Bahariya Formation (early Cenomanian), Bahariya
Oasis, Western Desert, Egypt. Journal of African Earth Sciences
51(2):89-103. doi: 10.1016/j.jafrearsci.2007.12.004.

ABSTRACT: The Lower Cenomanian Bahariya Formation in the Bahariya Oasis,
Western Desert, Egypt, was deposited under two coeval environmental
conditions. A fully fluvial system occurs in the southern portion of the
Bahariya Oasis, including depositional products of meandering and braided
streams, and a coeval fluvio-marine setting is dominant to the north. These
deposits are organized into four unconformity-bounded depositional
sequences, whose architecture is shaped by a complex system of incised
valleys. The fluvial portion of the lower two depositional sequences is
dominated by low-energy, meandering systems with a tabular geometry,
dominated by overbank facies. The fluvial deposits of the upper two
sequences represent the product of sedimentation within braided streams, and
consist mainly of amalgamated channel-fills. The braided fluvial systems
form the fill of incised valleys whose orientation follows a
southeast?northwest trending direction, and which truncate the underlying
sequences.
     Four sedimentary facies have been identified within the braided-channel
systems, namely thin-laminated sandstones (Sh), cross-bedded sandstones (Sp,
St), massive ferruginous sandstones (Sm) and variegated mudstones (Fm). The
exposed off-channel overbank facies of the meandering systems include
floodplain (Fm) and crevasse splay (Sl) facies. The fluvio-marine
depositional systems consist of interbedded floodplain, coastal and
shallow-marine deposits. The floodplain facies include fine-grained
sandstones (Sf), laminated siltstones (Stf) and mudstones (Mf) that show
fining-upward cycles. The coastal to shallow-marine facies consist primarily
of mudstones (Mc) and glauconitic sandstones (Gc) organized vertically in
coarsening-upward prograding cyclothems topped by thin crusts of ferricrete
(Fc). The four depositional sequences are present across the Bahariya Oasis,
albeit with varying degrees of preservation related to post-depositional
erosion associated with the formation of sequence boundaries. These
unconformities may be overlain by braided-stream channel sandstones at the
base of incised valleys, or marked by ferricrete paleosols (lithofacies Fc)
in the interfluve areas.





Schmeisser, R.L., and Flood, T.P. 2008. Recognition of paleogastroliths from
the Lower Cretaceous Cedar Mountain Formation, Utah using a scanning
electron microscope. Ichnos 15(2):72-77. doi: 10.1080/10420940801909118.

ABSTRACT: Paleogastroliths, as defined in this study, are stomach stones
associated exclusively with extinct animals. Definitive recognition of
paleogastroliths is problematic and controversial. Polished, rounded stones
found within skeletal remains of dinosaurs and plesiosaurs are the strongest
evidence. This study examined intraskeletal and proposed paleogastroliths
using a scanning electron microscope (SEM) to determine if any defining
surface textures occur. Paleogastroliths associated with the skeletal
remains of Seismosaurus hallorum, possible paleogastroliths from the Lower
Cretaceous Cedar Mountain Formation, and other well-polished stones were
obtained. Most stones were composed of either quartzite or chert and were
examined with a SEM at magnifications ranging from 100× to 400×. All of the
cherty Seismosaurus hallorum stones contained sets of parallel to
sub-parallel, curved polish grooves that in places crosscut one another.
These grooves are inferred to have formed as the result of small particles
lodged in the stomach muscles interacting with the stones due to muscle
movement. The distinctive surface textures noted on the cherty Seismosaurus
hallorum paleogastroliths are similar to those seen on the cherty possible
paleogastroliths from the Cedar Mountain Formation. Therefore, the geologic
occurrence combined with the microscopic surface texture supports the
interpretation that these stones are paleogastroliths.




Britt, B.B., Scheetz, R.D., and Dangerfield, A. 2008. A suite of dermestid
beetle traces on dinosaur bone from the Upper Jurassic Morrison Formation,
Wyoming, USA. Ichnos 15(2):59-71. doi: 10.1080/10420940701193284.

ABSTRACT: Most studies of insect traces on fossil bone deal with one or two
trace morphs found on isolated bone fragments, making it difficult to
identify the trace-maker and its behavior. We report the discovery of a
suite of insect traces on an articulated Camptosaurus dinosaur skeleton that
permits the identification of the trace-maker and interpretations of its
behavior. The traces include mandible marks, pits, and shallow bores on
cortical bone, and deep, meandering furrows and tunnels (borings) on
articular surfaces. The interiors of bones are intensely mined, and the
cavities and borings are filled with fine bone fragments (insect frass). The
distinctive mandible marks consist of opposing sets of parallel grooves,
indicating the maker had two apical teeth set on symmetrical mandibles and
that all of the traces were made by a single taxon. Comparison of the
fossils with the mandible morphology and bone traces of extant insects
indicates dermestid beetles made the traces. Based on extant dermestid
behavior, soft tissues were likely absent and the bones were lipid-laden
when the traces were made. Examination of more than 5,000 bones from the
Morrison and Cedar Mountain formations shows insect traces on bone are
common but overlooked and that many bones are substantially damaged by
insect mining. The key to the recognition of these important yet subtle
traces is a search model and an intense, oblique light source.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
 and     dinogami@gmail.com
http://cactus.dixie.edu/jharris/

"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
                                 --- Demetri Martin