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Brooklyn's Finest New Papers
Lee, Y.-N., Azuma, Y., Lee, H.-J., Shibata, M., and LÃ, J. 2009. The first
pterosaur trackways from Japan. Cretaceous Research. doi:
10.1016/j.cretres.2009.11.001.
ABSTRACT: In 1990, five well-preserved pterosaur trackways were discovered in
the Kitadani Formation (Lower Cretaceous) of the Kitadani Dinosaur Quarry,
Fukui Prefecture, Japan. They occur on the surface of an isolated dark grey
siltstone slab (70 Ã 50 cm) along with amphibian and bird tracks as well as
feeding marks. All pterosaur trackways (a total of 64 imprints) show a clear
quadrupedal gait pattern comprising manus and pes prints which reflect their
detailed anatomy of the feet. Manus and pes imprint is very small, average 22.6
mm and 21.9 mm long, respectively. The manus has an anteriorly oriented digit I
imprint with a medially oriented hook-like sharp claw mark, which makes a high
divarication (average 155.4Â) between the posteriorly oriented digit III
imprint. The high digital abduction clearly shows that digit I of the manus
could be more hyper-extended anteriorly than previously thought: spreading the
digits as much as possible would provide a more stable contact with substrate
as well as better support the center of pterosaur body mass displaced
anteriorly. The interdigital webbing of the pes imprint extends from the
metatarso-phalangeal joint near to the bases of four claws. As these features
clearly distinguish the Kitadani pterosaur trackways from five known
ichnospecies of Pteraichnus, we assign them to a new ichnospecies, Pteraichnus
nipponensis. Abundant small pterosaur ichnotaxa from Spain, Korea, and Japan
indicate that many small pterodactyloid pterosaur species existed in the Early
Cretaceous although there is no single skeletal datum yet.
Fox, R.C., and Scott, C.S. 2009. Comment on âA high latitude vertebrate fossil
assemblage from the Late Cretaceous of west-central Alberta, Canada: Evidence
for dinosaur nesting and vertebrate latitudinal gradientâ by F. Fanti and T.
Miyashita [Palaeogeography, Palaeoclimatology, Palaeoecology 275 (2009) 37-53].
Palaeogeography, Palaeoclimatology, Palaeoecology. doi:
10.1016/j.palaeo.2009.10.030.
ABSTRACT: A recent paper by Fanti and Miyashita (2009. A high latitude
vertebrate fossil assemblage from the Late Cretaceous of west-central Alberta,
Canada: evidence for dinosaur nesting and vertebrate latitudinal gradient.
Palaeogeography, Palaeoclimatology, Palaeoecology 275, 37-53) reports on a new
assemblage of terrestrial vertebrate fossils from the Campanian (Late
Cretaceous) of northern Alberta. In addition to the several dinosaur and
microvertebrate specimens reported by Fanti and Miyashita (2009), the new
assemblage also contains two mammalian teeth, identified by the authors as
pertaining to âCimolodon sp.â and âDidelphodon sp.â The taxonomic
identifications of these teeth are either highly questionable or simply
incorrect, and the accompanying descriptions are replete with errors; as a
result of these lapses, at least part of the biogeographic conclusions drawn by
the authors about the Kleskun Hills Park area is also rendered incorrect. While
the discovery of a Late Cretaceous high latitude vertebrate fauna in Alberta is
unquestionably important, the significance of the Kleskun Hills mammalian taxa,
both taxonomically and biogeographically, should be reconsidered.
Mayr, G. 2009. Response to Lingham-Soliar: dinosaur protofeathers: pushing back
the origin of feathers into the Middle Triassic? Journal of Ornithology. doi:
10.1007/s10336-009-0476-1.
ABSTRACT: Theagarten Lingham-Soliar, feather, dermal structure, integument,
skin, Theropoda, theropod, Aves, Avialae, avian, bird, evolution, phylogeny,
phylogenetics, origin, Lower Cretaceous, Early Cretaceous, Jehol, Yixian
Formation, China, Liaoning, Ceratopsia, ceratopsian, Psittacosauridae,
psittacosaurid, psittacosaur, Psittacosaurus,
Heimhofer, U., Ariztegui, D., Lenniger, M., Hesselbo, S.P., Martill, D.M., and
Rios-Netto, A.M. 2009. Deciphering the depositional environment of the
laminated Crato fossil beds (Early Cretaceous, Araripe Basin, North-eastern
Brazil). Sedimentology. doi: 10.1111/j.1365-3091.2009.01114.x.
ABSTRACT: The laminated limestones of the Early Cretaceous Crato Formation of
the Araripe Basin (North-eastern Brazil) are world-famous for their
exceptionally well-preserved and taxonomically diverse fossil fauna and flora.
Whereas the fossil biota has received considerable attention, only a few
studies have focused on the sedimentary characteristics and palaeoenvironmental
conditions which prevailed during formation of the Crato Fossil LagerstÃtte.
The Nova Olinda Member represents the lowermost and thickest unit (up to 10 m)
of the Crato Formation and is characterized by a pronounced rhythmically
bedded, pale to dark lamination. To obtain information on palaeoenvironmental
conditions, sample slabs derived from three local stratigraphic sections within
the Araripe Basin were studied using high-resolution multiproxy techniques
including detailed logging, petrography, Î-XRF scanning and stable isotope
geochemistry. Integration of lithological and petrographic evidence indicates
that the bulk of the Nova Olinda limestone formed via authigenic precipitation
of calcite from within the upper water column, most probably induced and/or
mediated by phytoplankton and picoplankton activity. A significant contribution
from a benthonic, carbonate-secreting microbial mat community is not supported
by these results. Deposition took place under anoxic and, at least during
certain episodes, hypersaline bottom water conditions, as evidenced by the
virtually undisturbed lamination pattern, the absence of a benthonic fauna and
by the occurrence of halite pseudomorphs. Input of allochthonous,
catchment-derived siliciclastics to the basin during times of laminite
formation was strongly reduced. The Î18O values of authigenic carbonate
precipitates (between â7Â1 and â5Â1â) point to a 18O-poor meteoric water source
and support a continental freshwater setting for the Nova Olinda Member. The
Î13C values, which are comparatively rich in 13C (between â0Â1 and +1Â9â), are
interpreted to reflect reduced throughflo!
w of wate
CO2, probably in concert with stagnant conditions and low input of soil-derived
carbon. Integration of lithological and isotopic evidence indicates a shift
from closed to semi-closed conditions towards a more open lake system during
the onset of laminite deposition in the Crato Formation.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/
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