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Various other papers of interest in the latest Palaeontology



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Palaeontology 51(4)

DARLA K. ZELENITSKY, FRANÇOIS THERRIEN
PHYLOGENETIC ANALYSIS OF REPRODUCTIVE TRAITS OF MANIRAPTORAN THEROPODS AND
ITS IMPLICATIONS FOR EGG PARATAXONOMY
807-816
DOI: 10.1111/j.1475-4983.2008.00770.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00770.x
AB: Abstract: A phylogenetic analysis of reproductive and oological (egg)
traits of theropod taxa allows determination of the sequence in which these
traits evolved in Theropoda. Our results indicate that several avian
reproductive traits, such as adults sitting on eggs, asymmetrical eggs,
unornamented eggshell surface, and complex eggshell ultrastructure, were
already present in non-avian maniraptorans, and could have evolved in more
basal theropods. In addition, non-avian maniraptorans laid two eggs at a
time and orientated their eggs subvertically or subhorizontally in their
nests, features not retained by neornithine birds. Based on our cladistic
analysis it is also possible to infer the phylogenetic affinity of ootaxa of
unknown parentage: Protoceratopsidovum was laid by a maniraptoran more
derived than oviraptorids, and Parvoolithus probably belonged to a
Cretaceous bird. Finally, our analysis reveals that many of the high-level
categories of egg parataxonomy (morphotypes and basic types) are unnatural
groupings (i.e. non-monophyletic). We recommend that these high-level
categories be abandoned because oofamilies are sufficient to categorize egg
taxa.



ANDREW B. HECKERT, SPENCER G. LUCAS, LARRY F. RINEHART, ADRIAN P. HUNT
A NEW GENUS AND SPECIES OF SPHENODONTIAN FROM THE GHOST RANCH
<i>COELOPHYSIS</i> QUARRY (UPPER TRIASSIC: APACHEAN), ROCK POINT FORMATION,
NEW MEXICO, USA
827-845
DOI: 10.1111/j.1475-4983.2008.00786.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00786.x
AB: Abstract: We document here a new taxon of sphenodontian, Whitakersaurus
bermani gen. et sp. nov., that is also the most complete sphenodontian
fossil from the Upper Triassic Chinle Group in the south-western USA and the
first Chinle sphenodontian represented by more than a single fragmentary
dentulous element. The holotype was recovered during preparation of block
C-8-82 from the famous Coelophysis (Whitaker) quarry at Ghost Ranch, New
Mexico, and is the most complete small vertebrate recovered from the quarry.
Detailed lithostratigraphy and geologic mapping demonstrate that the
Whitaker quarry is in the Rock Point Formation of the Chinle Group, so
Whitakersaurus is the first sphenodontian reported from this unit. Records
of the phytosaur Redondasaurus at the quarry and elsewhere in the Chinle
Group demonstrate that the quarry, and thus Whitakersaurus, is of Apachean
(late Norian2013Rhaetian) age. The sphenodontian specimen consists of
incomplete left and right dentaries, a partial left? maxilla?, and
impressions of a probable palatal element, all of which preserve multiple
teeth. Whitakersaurus is distinct from other sphenodontians in possessing a
unique combination of the following features: marginal dentition pleurodont
anteriorly and posteriorly acrodont; pronounced heterodonty in dentary, with
as many as 15 smaller, peg-like teeth anteriorly and several larger,
posterior teeth that are conical and striated; faint radial ornamentation of
posterior tooth crowns; presence of c. 19 dentary teeth; and absence of a
distinct flange on posterior teeth. Numerous other details distinguish it
from both more primitive and more derived taxa. Whitakersaurus, therefore,
helps to document further mosaic evolution and an extensive diversification
event of sphenodontians during Triassic time. Although sphenodontian taxa
are relatively easily recognized, widely distributed, and common small- or
microvertebrate fossils, the long stratigraphic ranges of taxa known from
multiple specimens hinders their utility as index fossils with which to
correlate strata across Pangaea.


LEONARDO SALGADO, ISMAR DE SOUZA CARVALHO
UBERABATITAN RIBEIROI, A NEW TITANOSAUR FROM THE MAR&Iacute;LIA FORMATION
(BAURU GROUP, UPPER CRETACEOUS), MINAS GERAIS, BRAZIL
881-901
DOI: 10.1111/j.1475-4983.2008.00781.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00781.x
AB: Abstract: A new Late Cretaceous titanosaur sauropod from the Bauru Basin
of Brazil, Uberabatitan ribeiroi gen. et sp. nov., represented by at least
three specimens, is described. The material comes from a level of coarse
sandstone within the Serra da Galga sequence in Uberaba County, Minas Gerais
State. The fossiliferous strata belong to the Marília Formation (Serra da
Galga Member), Bauru Group, considered to be Maastrichtian in age. The
fossils occur in the uppermost levels of the above-mentioned unit; thus,
Uberabatitan ribeiroi is the youngest titanosaur to have been recorded from
the Bauru Basin. The autapomorphies that support the new species are: (1)
anterior and mid-cervicals with postzygodiapophyseal lamina (podl) segmented
in zygapophyseal and diapophyseal laminae, of which the first extends
rostrodorsally over the second; (2) mid-dorsals with a robust lateral lamina
formed mainly by a diapophyseal lamina (probably homologous to the
postzygodiapophyseal lamina), and, to a lesser extent, by a relic of the
spinodiapophyseal lamina (spdl); (3) mid (and probably posterior) dorsals
with accessory neural laminae, which are lateral to the prespinal lamina,
and probably homologous to the spinoprezygapophyseal laminae (sprl); (4)
mid-caudal centra with deeply excavated lateral faces; (5) pubis very thick
and robust, with a very stout longitudinal crest on its external (ventral)
face; and (6) proximal end of the tibia with a prominent lateral
protuberance, which articulates with an equally prominent medial knob of the
fibula. The titanosaurian assemblage at Uberaba includes, apart from U.
ribeiroi, well-preserved specimens assigned to species of uncertain
affinities (Trigonosaurus pricei and Baurutitan britoi), as well as a few
vertebrae assigned to aeolosaurines.


KOEN STEIN, COLIN PALMER, PAMELA G. GILL, MICHAEL J. BENTON
THE AERODYNAMICS OF THE BRITISH LATE TRIASSIC KUEHNEOSAURIDAE
967-981
DOI: 10.1111/j.1475-4983.2008.00783.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00783.x
AB: Abstract: The Kuehneosauridae (Late Triassic, Britain, USA) had
remarkable adaptations, most notably their elongate mid-dorsal ribs that
were presumably covered with a skin membrane in life. These lateral 'wings'
have always been linked with some form of gliding adaptation, but
quantitative studies have been limited. Here, we provide a thorough
aerodynamic analysis of both genera of British kuehneosaurids based on
theory and on experiments with life-sized models in a wind tunnel. Of the
two genera, Kuehneosuchus, with elongate 'wings', was a glider, and
Kuehneosaurus, with much shorter 'wings', was a parachutist. Kuehneosuchus
most probably had highly cambered wings and no additional skin membranes on
hands or feet, nor did it have a cruropatagium. Lappets on the hyoid
apparatus, as seen in Draco, were probably present to enhance pitch control.
Kuehneosuchus was capable of gliding at angles (03B8) between 13 and 16
degrees, at speeds between 7 and 9 m/s, and was probably very manoeuvrable
when airborne. Kuehneosaurus was capable of parachuting (03B8 &gt; 45
degrees) at speeds between 10 and 12 m/s. It is unclear whether the British
kuehneosaurid material represents two genera, as assumed here, two species
of one genus, or sexual dimorphs of a single species, where the gliding
Kuehneosuchus was the male, which used its gliding and perhaps highly
coloured 'wings' to display to the parachuting Kuehneosaurus.

NICK LONGRICH
A NEW, LARGE ORNITHOMIMID FROM THE CRETACEOUS DINOSAUR PARK FORMATION OF
ALBERTA, CANADA: IMPLICATIONS FOR THE STUDY OF DISSOCIATED DINOSAUR REMAINS
DOI: 10.1111/j.1475-4983.2008.00791.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00791.x
AB: Abstract: Only two ornithomimid genera, Ornithomimus and Struthiomimus,
are currently known from the Upper Cretaceous of North America. However, a
number of ornithomimid elements from Alberta's Dinosaur Park Formation
(Upper Campanian), cannot be assigned to either Ornithomimus or
Struthiomimus. These bones, including a frontal, caudal vertebrae, and
unguals of the manus and the pes, come from animals significantly larger
than any previously known Judithian ornithomimid. The frontal exhibits
several unusual features, including transverse expansion over the
prefrontals, and extreme reduction of the supratemporal fossae. Caudal
vertebrae are characterized by neural arches that are posteriorly shifted
and transversely expanded. Manual unguals possess a highly concave articular
surface, a flexor tubercle divided by a sulcus, and a broad claw. Pedal
unguals display highly concave articular surfaces, and a ridge-like flexor
tubercle dividing a deep ventral fossa. Although it is difficult to know
whether these elements represent a single taxon, this is currently the most
parsimonious hypothesis. This study demonstrates how isolated dinosaur bones
can extend our knowledge of dinosaur faunas.


KARL T. BATES, PHILLIP L. MANNING, BERNAT VILA, DAVID HODGETTS
THREE-DIMENSIONAL MODELLING AND ANALYSIS OF DINOSAUR TRACKWAYS
999-1010
AD: Faculty of Life Sciences, University of Manchester, Jacksons Mill, PO
Box 88, Sackville Street, Manchester M60 1QD, UK; e-mail:
karl.bates@postgrad.manchester.ac.uk;  School of Earth, Atmospheric and
Environmental Sciences, University of Manchester, Williamson Building,
Oxford Road, Manchester M13 9PL, UK; e-mails: phil.manning@manchester.ac.uk,
david.hodgetts@manchester.ac.uk;  The Manchester Museum, University of
Manchester, Oxford Road, Manchester M13 9PL, UK;  Institut Catal de
Paleontologia, C Escola Industrial, 23, 08201 Sabadell, Barcelona, Spain;
e-mail: bernat.vila@icp.cat
DOI: 10.1111/j.1475-4983.2008.00789.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00789.x
AB: Abstract: Light Detection And Range (LiDAR) imaging provides a means to
model the 3D geometry of fossil tracks in the field with high accuracy. This
represents a considerable advance for the science of vertebrate ichnology in
which traditional field methods suffer from a significant degree of
abstraction and lack the resolution required to interpret tracks
quantitatively. Three-dimensional LiDAR models provide additional
morphometric information and allow the application of new analytical tools
unique to the digital environment. The method will enable fossil track
morphometrics to develop into an iterative process that combines 3D
visualization and multivariate statistical methods, blending qualitative and
quantitative approaches and allowing track morphologies to be compared
holistically. Modelling of trackways from Fumanya (south-east Pyrenees)
using LiDAR has enabled variation in linear track dimensions to be explained
by the varied contribution of different modes of shear with increasing depth
below the foot/sediment interface. Features in the relief of pes traces
indicate that subsurface zones within their track volumes are defined by the
interaction of puncture and local shear, below a surface zone of
liquefaction failure now lost to erosion. This model of mechanical failure
enables a preliminary review of the pedal kinematics of titanosaurid
sauropod dinosaurs and suggests multiphase loading of the sediment by the
titanosaurid pes. However, from inspection of these 3D surfaces alone it is
not possible to differentiate between the possibility of one or two discrete
phases of pedal motion preceding the toe-off event at the maximum height of
the support phase. By integrating LiDAR models with analogue modelling
within a 3D digital environment it will be possible to clarify such
interpretations of fossil tracks and the locomotor mechanics of extinct
animals.


FERNANDO ABDALA, BRUCE S. RUBIDGE, JURI van den HEEVER
THE OLDEST THEROCEPHALIANS (THERAPSIDA, EUTHERIODONTIA) AND THE EARLY
DIVERSIFICATION OF THERAPSIDA
1011-1024
DOI: 10.1111/j.1475-4983.2008.00784.x
US: http://dx.doi.org/10.1111/j.1475-4983.2008.00784.x
AB: Abstract: The oldest records of mammal-like therapsids in Laurasia are
from the Ocher Complex of Russia and the Xidagou Formation of China, whereas
in Gondwana they are restricted to the Eodicynodon Assemblage Zone, Beaufort
Group of the South African Karoo. This fauna, which is relatively
depauperate when compared with younger assemblage zones from the Karoo,
shows an amazing diversity of therapsids including: dinocephalians (already
represented by the carnivorous anteosaurids and the herbivorous
tapinocephalids), anomodonts (including dicynodonts), gorgonopsians, and
therocephalians. The last group is represented by two specimens in this
assemblage zone. This paper presents a full description of these
therocephalians, which are assigned to the scylacosaurid species Glanosuchus
macrops and Ictidosaurus angusticeps. We also discuss diversity trends of
therocephalians and explore some hypotheses implicated by the diverse oldest
record of therapsids, represented by five of the six major lineages of the
group.

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661               

Faculty Director, Earth, Life & Time Program, College Park Scholars
http://www.geol.umd.edu/~jmerck/eltsite/
Fax: 301-405-0796

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA