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Juravenator "proto-feathers" and other new papers
From: Ben Creisler
bh480@scn.org
In case these articles have not been mentioned yet:
Chiappe, Luis M.; Göhlich, Ursula B.
Anatomy of Juravenator starki (Theropoda: Coelurosauria)
from the Late Jurassic of Germany.
Neues Jahrbuch für Geologie und Paläontologie -
Abhandlungen, 258(3): 257-296 (December 2010)
DOI: 10.1127/0077-7749/2010/0125
We provide a detailed study of the morphology of the
holotype of Juravenator starki from the Late Jurassic of
the Solnhofen area of southern Germany. The incompletely
ossified surface of multiple bones and lack of several
skeletal fusions indicate that Juravenator starki is
based on an immature specimen. Nonetheless, numerous
unique morphologies and bone proportions distinguish this
taxon from Compsognathus longipes, the only previously
named non-avian theropod dinosaur from the Late Jurassic
of the Solnhofen Archipelago. Yet, its skeletal anatomy
is most similar to that of Compsognathus and other
theropods that have often been regarded as closely
related to the latter - sometimes within a monophyletic
Compsognathidae. Juravenator is characterized by having a
small size (∼ 0.75-meter-long in the holotype) with few
maxillary teeth, lack of a premaxillary-maxillary
diastema, an antorbital fenestra subequal in length to
orbit, an elongate scapula that is narrowest at its neck,
a proportionally short humerus and high and abruptly
tapered manual claws, and bow-like zygapophysial
articulations in the mid-caudal vertebrae. Portions of
the epidermis preserved mainly along the tail provide the
only glimpse of the morphology of the skin of basal
coelurosaurs, and structures newly revealed under UV
light hint at the possibility of filamentous
integumentary structures - akin to those interpreted as
proto-feathers in other basal coelurosaurs - also
covering the body of this dinosaur. The discovery of
Juravenator has provided evidence of morphologies - from
details of the skull to the epidermis - that are poorly
known in other theropods interpreted as at or near the
base of Coelurosauria, and thus contributes significantly
to our understanding of the evolutionary history of this
clade. The exquisitely preserved holotipic skeleton adds
significantly to the meager record of small-bodied Late
Jurassic theropods.
http://www.ingentaconnect.com/content/schweiz/njbgeol/2010
/00000258/00000003/art00001
The Paludititan paper also officially published in this
issue of Neues Jahrbuch, but it's been available for a
time online already and discussed in the DML.
Also, since the Koreanosaurus paper was NOT published in
the December issue, it means that the official
publication date will be in 2011.
====================
Michael E. Burns, Philip J. Currie, Robin L. Sissons and
Victoria M. Arbour (2010)
Juvenile specimens of Pinacosaurus grangeri Gilmore, 1933
(Ornithischia: Ankylosauria) from the Late Cretaceous of
China, with comments on the specific taxonomy of
Pinacosaurus.
Cretaceous Research (advance publication)
doi:10.1016/j.cretres.2010.11.007
Four juvenile specimens referable to Pinacosaurus
grangeri (Ankylosauria: Dinosauria) are described from
the Campanian (Upper Cretaceous) locality Bayan Mandahu
in northern Inner Mongolia Autonomous Region (People's
Republic of China). The specimens all preserve the skulls
as well as, in some cases, mandibles, postcrania, and
armour. They are not taphonomically deformed by expanding
matrix distortion, unlike many Gobi specimens, including
the holotype of P. grangeri. Bayan Mandahu is also the
type locality for Pinacosaurus mephistocephalus. The
proximity in space and time of these two closely related
species warrants a generic and specific revision for
Pinacosaurus. The distinction of the two species is based
on characters of the squamosal dermal elaborations,
cranial roof posterior to the orbits, premaxillary notch,
and distal margin of the ilium. Although a relatively
well-represented ankylosaur taxon, the phylogenetic
position of Pinacosaurus has not been unequivocally
resolved. A new analysis recovers Pinacosaurus as the
most basal member of the Ankylosaurinae.
http://www.sciencedirect.com/science?
_ob=ArticleURL&_udi=B6WD3-51J9DCH-
1&_user=10&_coverDate=11%2F24%
2F2010&_rdoc=3&_fmt=high&_orig=browse&_origin=browse&_zone
=rslt_list_item&_srch=doc-info(%23toc%236755%239999%
23999999999%2399999%23FLA%23display%23Articles)
&_cdi=6755&_sort=d&_docanchor=&_ct=14&_acct=C000050221&_ve
rsion=1&_urlVersion=0&_userid=10&md5=d37d79eedabc5c9638588
84dcb0718a5&searchtype=a
Martin G. Lockley, Ri-Hui Li, , Masaki Matsukawa, Mingwei
Liu and Kebai Wang (2010)
An unusual theropod track assemblage from the Cretaceous
of the Zhucheng area, Shandong Province, China.
Cretaceous Research (advance publication)
doi:10.1016/j.cretres.2010.10.006
More than 125 footprints of theropods from the Cretaceous
Longwangzhuang Formation have been mapped in a
preliminary study at a site in the Zhucheng region of
China. The tracks represent at least three morphotypes.
The largest morphotype is a large theropod (footprint
length ?30 cm) represented by a single trackway and an
isolated natural cast. At least 10 trackways assigned to
the new ichnospecies Corpulentapus lilasia represent a
medium-sized biped (footprint length ?13 cm) with very
short,wide, robust, ?tulip-shaped? tracks and long steps
(?5 x footprint length), and a short central digit (III)
indicating weak mesaxony. Corpulentapus trackways are
narrow and theropod-like even though track morphology is
convergent with the footprints of some ornithopods. The
third morphotype, made by a medium-sized grallatorid
track maker (ichnogenus Paragrallator), is about the same
size (? 13 cm) as the robust morphotype, but far more
elongate and gracile, with an elongate central digit
(III) indicating strong mesaxony. This ichnotaxon
requires detailed comparison with Grallator sensu
stricto.The contrast in morphology between the two common
morphotypes is striking and demonstrates that two
distinct medium-sized taxa of presumed theropod affinity
frequented the same habitat in significant numbers. No
non-theropod tracks are currently known from this
locality.
http://www.sciencedirect.com/science?
_ob=ArticleURL&_udi=B6WD3-51JPWJ9-
2&_user=10&_coverDate=11%2F26%
2F2010&_rdoc=2&_fmt=high&_orig=browse&_origin=browse&_zone
=rslt_list_item&_srch=doc-info(%23toc%236755%239999%
23999999999%2399999%23FLA%23display%23Articles)
&_cdi=6755&_sort=d&_docanchor=&_ct=14&_acct=C000050221&_ve
rsion=1&_urlVersion=0&_userid=10&md5=e264a73470b9e1897dd57
3b1c589f182&searchtype=a
Anthony Romilio and Steven W. Salisbury (2010)
A reassessment of large theropod dinosaur tracks from the
mid-Cretaceous (late Albian?Cenomanian) Winton Formation
of Lark Quarry, central-western Queensland, Australia: A
case for mistaken identity
Cretaceous Research (advance publication)
doi:10.1016/j.cretres.2010.11.003
Multivariate analysis is used to differentiate shape
variations between ichnites of theropod and ornithopod
dinosaurs. Tracks of an alleged theropod cf.
Tyrannosauropus from the mid-Cretaceous (late Albian?
Cenomanian) Winton Formation of Lark Quarry, central-
western Queensland, Australia were examined and foot
shape ratios calculated. Multivariate analysis of these
shape variables indicates this track-maker was an
ornithopod dinosaur. A strong morphological similarity
exists between the Lark Quarry ichnites and those of the
iguanodontian ichnotaxon Amblydactylus gethingi.
Considering the grade of ornithopod this ichnogenus is
thought to represent (a non-hadrosaurid styracosternan)
and the age and geography of Lark Quarry, we suggest that
the track-maker may have been a dinosaur similar to
Muttaburrasaurus langdoni.