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Where The New Papers Are

Upchurch, P., and Mannion, P.D. 2009. The first diplodocid from Asia and its 
implications for the evolutionary history of sauropod dinosaurs. Palaeontology. 
doi: 10.1111/j.1475-4983.2009.00909.x.

ABSTRACT: An isolated anterior caudal vertebra from the Qingshan (= Ch'ing 
shan) Formation (Early Cretaceous) of Shandong Province, China, is redescribed 
and shown to be an advanced diplodocid sauropod. This specimen possesses 
several derived character states that are typically observed in advanced 
diplodocoids or diplodocids, including the following: a mildly procoelous 
centrum; a deep pit-like pneumatic fossa immediately below the caudal rib; 
wing- or fan-shaped caudal ribs; and complex lamination of the neural spine. 
The neural spine is apomorphically short and the centrum is short relative to 
its height compared to those of other diplodocids, which, when coupled with the 
specimen's unique geographical location and stratigraphical age, suggests that 
it probably represents a new taxon. This caudal vertebra provides the first 
convincing evidence that diplodocids were present in Asia, perhaps as a result 
of the dispersal of neosauropod lineages from Europe and/or North America 
during the Early Cretaceous. The discovery of a member of the Diplodocidae in 
the Early Cretaceous also indicates that this clade did not become extinct at 
the Jurassic/Cretaceous boundary as previously supposed.

Benson, R.B.J., Carrano, M.T., and Brusatte, S.L. 2009. A new clade of archaic 
large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to 
the latest Mesozoic. Naturwissenschaften. doi: 10.1007/s00114-009-0614-x.

ABSTRACT: Non-avian theropod dinosaurs attained large body sizes, monopolising 
terrestrial apex predator niches in the JurassicâCretaceous. From the Middle 
Jurassic onwards, Allosauroidea and Megalosauroidea comprised almost all 
large-bodied predators for 85 million years. Despite their enormous success, 
however, they are usually considered absent from terminal Cretaceous 
ecosystems, replaced by tyrannosaurids and abelisaurids. We demonstrate that 
the problematic allosauroids Aerosteon, Australovenator, Fukuiraptor and 
Neovenator form a previously unrecognised but ecologically diverse and globally 
distributed clade (Neovenatoridae, new clade) with the hitherto enigmatic 
theropods Chilantaisaurus, Megaraptor and the Maastrichtian Orkoraptor. This 
refutes the notion that allosauroid extinction pre-dated the end of the 
Mesozoic. Neovenatoridae includes a derived group (Megaraptora, new clade) that 
developed long, raptorial forelimbs, cursorial hind limbs, appendicular 
pneumaticity and small size, features acquired convergently in bird-line 
theropods. Neovenatorids thus occupied a 14-fold adult size range from 175 kg 
(Fukuiraptor) to approximately 2,500 kg (Chilantaisaurus). Recognition of this 
major allosauroid radiation has implications for Gondwanan paleobiogeography: 
The distribution of early Cretaceous allosauroids does not strongly support the 
vicariant hypothesis of southern dinosaur evolution or any particular 
continental breakup sequence or dispersal scenario. Instead, clades were nearly 
cosmopolitan in their early history, and later distributions are explained by 
sampling failure or local extinction.

Moratalla, J.J. 2009. Sauropod tracks of the Cameros Basin (Spain): 
identification, trackway patterns and changes over the Jurassic-Cretaceous. 
Geobios. doi: 10.1016/j.geobios.2009.06.006.

ABSTRACT: Sauropod tracks make up only about 2% of the Cameros Basin 
ichnocenosis, but they are present over the entire time span represented by the 
Cameros sediments. The makers of these tracks are identified in terms of their 
associated trackway pattern as either wide or narrow-gauge morphotypes. 
Narrow-gauge trackways dominate the Tithonian-Berriasian interval. Wide-gauge 
trackways become notably more common after the Berriasian, although 
narrow-gauge trackways are still present and dominate the Cameros ecosystems 
even during the Aptian. At this time an interesting equilibrium between 
titanosauriform and non-titanosauriform sauropod trackways is evident, although 
the latter are somewhat more common.
     A review of the Iberian sauropod bone record suggests that Turiasauria + 
Euhelopidae, Rebbachisauridae and Titanosauriformes are the three groups mainly 
responsible for the Cameros Basin sauropod ichnocenosis.

D'Amore, D.C., and Blumenschine, R.J. 2009. Komodo monitor (Varanus 
komodoensis) feeding behavior and dental function reflected through tooth marks 
on bone surfaces, and the application to ziphodont paleobiology. Paleobiology 
35(4):525-552. doi: 10.1666/0094-8373-35.4.525.

ABSTRACT: Most functional interpretations of ziphodont dentition are based on 
limited morphometric, behavioral, and taphonomic studies, but few are based on 
controlled observations of a modern ziphodont consumer. The purpose of this 
study is to determine through controlled feeding observations if the behaviors 
indicative of a ziphodont consumer are reflected by tooth marks left on bone 
surfaces by Varanus komodoensis, the Komodo monitor. We document feeding 
behavior, expand upon dental function, and correlate these aspects with tooth 
mark production. We also discuss the significance and limits of applying these 
data to fossil assemblages.
     Goat carcasses were fed to 11 captive individuals. V. komodoensis modifies 
bone surfaces extensively. Individuals exhibit a âmedial-caudal arcâ when 
defleshing, followed by inertial swallowing. Bone crushing was not observed. 
The vast majority of tooth marks are scores, with pits being significantly less 
common. Tooth furrows and punctures are rare. âEdge marksâ are produced on flat 
elements. Marks are elongate and narrow, with variable lengths and curvature. 
Over one-third of the marks occur within parallel clusters. Striations are 
evident on 5% of all marks.
     Both feeding behavior and tooth marks indicate that ziphodont crowns are 
ideal for defleshing by being drawn distally through a carcass. Crowns are 
poorly built for crushing, and within-bone nutrients are acquired through 
swallowing. Mark production is a by-product of the distal crown movement during 
the flesh removal process. Scores are the consequence of apical dragging. Edge 
marks and striated scores result respectively from distal and mesial carinae 
contact. Mark curvature is the consequence of arcing motions. Parallel clusters 
may result from repetitive defleshing strokes and/or from multiple crown 
contacts during a stroke.
     These observations can be used to draw functional, behavioral, and 
taphonomic interpretations from fossil assemblages. When they are provisionally 
applied to theropod tooth marks, similar crown function and defleshing behavior 
with little bone crushing is apparent. Differences occur concerning mark 
frequency and curvature, relating potentially to taphonomic biases and rostral 
motion, respectively.

Ji, Q., Ji, S.-A., and Zhang, L.-J. 2009. First large tyrannosauroid theropod 
from the Early Cretaceous Jehol Biota in northeastern China. Geological 
Bulletin of China 28(10):1369-1374. 

     (âerects _Sinotyrannus kazuoensis_ from the Jiufotang Formation)

Xing, L.-D., Dong, H., Peng, G.-Z., Shu, C.-K., Hu, X.-D., and Jiang, H. 2009. 
A scapular facture in Yangchuanosaurus hepingensis (Dinosauria: Theropoda). 
Geological Bulletin of China 28(10):1390-1395.

Jourdan, F., Renne, P.R., and Reimold, W.U. 2009. An appraisal of the ages of 
terrestrial impact structures. Earth and Planetary Science Letters 
286(1-2):1-13. doi: 10.1016/j.epsl.2009.07.009.

ABSTRACT: There are 174 confirmed impact structures known on Earth (e.g., 
http://www.unb.ca/passc/ImpactDatabase/; late 2008) but a far smaller number of 
impact structures has yielded a well-constrained age. Precise and accurate age 
constraints are crucial for (1) correlating causes and effects on the bio- and 
geosphere of catastrophic processes, (2) better constraining the impactor flux 
through geological time and evaluation of potential impact periodicity, (3) 
calibrating the absolute chronostratigraphic time scale, (4) calibrating the 
age of within-crater continental sedimentary deposits (e.g., for regional 
paleo-climatic analysis), and (5) correlating impact events and distal impact 
ejecta occurrences.
     Of these 174 listed impact structures only a few have precisely 
constrained ages (mostly obtained using radio-isotopic techniques, e.g. U/Pb 
and 40Ar/39Ar), with only 25 ages having a stated precision better than  2%, 
and a mere 16 ages with a precision better than  1%. Yet, even the accuracy of 
some of these ages can be challenged and probably improved based on more 
detailed interpretations and statistically more rigorous data analysis. 
Although geochronologists are often circumspect and advise caution in accepting 
calculated ages, these ages tend to propagate into the literature without 
further critical evaluation, are considered ârobustâ, and become widely 
accepted ages. A review of the age data for the 25 short-listed structures 
suggests that 11 ages are accurate, 12 are at best ambiguous and should not be 
reported with any uncertainty, and 2 are not well characterized at all. We 
report detailed examples of misleading ages and/or age uncertainties (e.g., 
poor stratigraphic constraints, data over-interpretations, ambiguity due to 
inconsistent results), and highlight the robustness of the 11 well-defined 
ages. Based on observations and modeling, suggestions are made on how to obtain 
better ages by carrying out adequate sample preparation. We also indicate how 
to interpret ages for non-geochronologists. This brief review should be 
interpreted as a call for immediate, drastic qualitative and quantitative 
improvements of the ages of terrestrial impact structures.

Godefroit, P., Codrea, V., and Weishampel, D.B. 2009. Osteology of Zalmoxes 
shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper 
Cretaceous of NÄlaÅ-Vad (Romania). Geodiversitas 31(3):525-553.

ABSTRACT: NÄlaÅ-Vad is a new fossil locality discovered in 2002 in the SÄnpetru 
Formation (Maastrichtian, Late Cretaceous) of the HaÅeg Basin (Transylvania, 
Romania). This site has, among others, yielded the most complete skeleton that 
can be referred to the ornithopods dinosaur Zalmoxes shqiperorum Weishampel, 
Jianu, Cziki & Norman, 2003, but also isolated elements belonging to both 
juveniles and adult individuals. This material provides new information about 
the anatomy of Z. shqiperorum, and about the inter- and intraspecific 
variability within Zalmoxes. Zalmoxes robustus (Nopsca, 1902) and Z. 
shqiperorum were apparently sympatric species in Transylvania by latest 
Cretaceous time. The co-existence in the same locality of two closely-related 
species is not an isolated case among ornithopod dinosaurs.

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

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