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A New Papers Carol
van der Lubbe, T., Richter, U., and KnÃtschke, N. 2009. Velociraptorine
dromaeosaurid teeth from the Kimmeridgian (Late Jurassic) of Germany. Acta
Palaeontologica Polonica 54(3):401-408. doi: 10.4202/app.2008.0007.
ABSTRACT: Six theropod teeth from a Late Jurassic (Kimmeridgian) bone bed in
Langenberg Quarry of Oker (Goslar, Germany) are identified as a new
dromaeosaurid taxon, here left in open nomenclature. Direct comparison reveals
that the teeth are very similar to velociraptorine dromaeosaurid teeth from the
Guimarota coal mine (Late Jurassic, Portugal) and to velociraptorine
dromaeosaurid teeth from UÃa (Barremian, Cuenca Province, Spain). Our data
indicate that the teeth from the Kimmeridgian of Lower Saxony are of
velociraptorine dromaeosaurid type, and therefore represent one of the oldest
occurrences of the group Dromaeosauridae.
Santos, V.F., Moratalla, J.J., and Royo-Torres, R. 2009. New sauropod trackways
from the Middle Jurassic of Portugal. Acta Palaeontologica Polonica
54(3):409-422. doi: 10.4202/app.2008.0049.
ABSTRACT: The Galinha tracksite reveals a sequence of BajocianâBathonian
limestones belonging to the Serra de Aire Formation (WestâCentral Portugal) and
is one of the few sites in the world where Middle Jurassic sauropod dinosaur
tracks can be found. This tracksite is characterised by the presence of long,
wide gauge sauropod trackways, the Middle Jurassic age of which suggests these
dinosaurs were more widely distributed over time than previously thought. Two
trackways contain unique pes and manus prints with morphologies that allow a
new sauropod ichnotaxon to be described: Polyonyx gomesi igen. et isp. nov. On
the basis of different manus/pes prints and trackway features, the proposal is
made to subdivide Sauropodomorpha ichnoâmorphotypes into five groups:
Tetrasauropusâlike, Otozoumâlike, Breviparopus/Parabrontopodusâlike;
Brontopodusâlike, and Polyonyxâlike. Polyonyx gomesi igen. et isp. nov. is
thought to represent a nonneosauropod eusauropod, with a well developed manus
digit I. The posterior orientation of this digit print suggests they were made
by a eusauropod dinosaur with a posteriorly rotated pollex. The manus print
morphologies observed in two trackways suggest a stage of manus structure
intermediate between the primitive nonâtubular sauropod manus and the tubular
metacarpal arrangement characteristic of more derived sauropods. The low
heteropody (manus:pes area ratio 1:2) of the trackway renders it possible they
could have been made by eusauropods such as Turiasaurus riodevensis, which has
a similar manus:pes area ratio. The Polyonyx igen. nov. trackway was made by
nonâneosauropod eusauropod, and suggests that wide gauge sauropod trackways
were not exclusively made by Titanosauriformes.
Averianov, A., and Sues, H.-D. 2009. First record of a basal neoceratopsian
dinosaur from the Late Cretaceous of Kazakhstan. Acta Palaeontologica Polonica
54(3):553-556. doi: 10.4202/app.2008.0079.
ABSTRACT: The oldest known ceratopsians come from the Late Jurassic of China
(Zhao et al. 1999; Xu et al. 2006). During the Early Cretaceous, the basal
ceratopsian Psittacosaurus was among the most common dinosaurs in Asia but more
derived basal neoceratopsians were quite rare on that continent (Xu et al.
2002; Makovicky and Norell 2006). Basal neoceratopsians became more abundant in
the Late Cretaceous of Mongolia and China, although they are not known in this
region from the latest Cretaceous (You and Dodson 2004; Alifanov 2008). In
contrast, basal neoceratopsians are rare during the Early Cretaceous in North
America but became common and diverse during the Campanian and Maastrichtian
(You and Dodson 2004; Chinnery and Horner 2007). Little is known about the
evolutionary history of this group in more inland regions of what are now
Kazakhstan and adjoining countries. Asiaceratops documents the presence of
basal neoceratopsians in the Cenomanian of Uzbekistan (Nessov et al. 1989).
Here we report on the first record of a basal neoceratopsian in the Late
Cretaceous of Kazakhstan, based on two cranial bones from the Turonian
Zhirkindek Formation in the northeastern Aral Sea region.
Benson, R.B.J., and Radley, J.D. 2009. A new large-bodied theropod dinosaur
from the Middle Jurassic of Warwickshire, United Kingdom. Acta Palaeontologica
Polonica. doi: 10.4202/app.2009.0083.
ABSTRACT: Previously undocumented postcranial material from the Chipping Norton
Limestone Formation (Middle Jurassic: Lower Bathonian) of Cross Hands Quarry,
near Little Compton, Warwickshire represents a new large-bodied theropod
dinosaur, distinct from the contemporaneous Megalosaurus bucklandii.
Cruxicheiros newmanorum gen. et sp. nov. is diagnosed by a single autapomorphy,
the presence of a proximomedially inclined ridge within the groove that marks
the lateral extent of the posterior flange of the femoral caput (trochanteric
fossa). C. newmanorum shows three tetanuran features: widely separated cervical
zygapophyses, a swollen ridge on the lateral surface of the iliac blade and an
anterior spur of the caudal neural spines. However, due to fragmentary
preservation its affinities within Tetanurae remain uncertain: phylogenetic
analysis places it as the most basal tetanuran, the most basal megalosauroid (=
spinosauroid) or the most basal neotetanuran.
Mateus, O., Jacobs, L., Polcyn, M., Schulp, A.S., Vineyard, D., Buta Neto, A.,
and Telles Antunes, M. 2009. The oldest African eucryptodiran turtle:
Angolachelys ombeu, from the Cretaceous of Angola. Acta Palaeontologica
Polonica. doi: 10.4202/app.2008.0063.
ABSTRACT: A new Late Cretaceous turtle, Angolachelys ombeu gen. et sp. nov.,
from the Turonian (90 Mya) of Angola, represents the oldest eucryptodire from
Africa. Phylogenetic analysis recovers Angolachelys ombeu as the sister taxon
of Sandownia harrisi from the Aptian of Isle of Wight, England. An unnamed
turtle from the Albian Glen Rose Formation of Texas (USA) and the Kimmeridgian
turtle Solnhofia parsonsi (Germany), are successively more distant sister taxa.
Bootstrap analysis suggests those four taxa together form a previously
unrecognized monophyletic clade of marine turtles, herein named Angolachelonia
n. clade, supported by the following synapomorphies: mandibular articulation of
quadrate aligned with or posterior to the occiput, and basisphenoid not visible
or visibility greatly reduced in ventral view. Basal eucryptodires and
angolachelonians originated in the northern hemisphere, thus Angolachelys
represents one of the first marine amniote lineages to have invaded the South
Atlantic after separation of Africa and South America.
Dias-da-Silva, S., and Ramos Ilha, A.L. 2009. On the presence of a pustulated
temnospondyl in the Lower Triassic of southern Brazil. Acta Palaeontologica
Polonica. doi: 10.4202/app.2008.0073.
ABSTRACT: The fossil record of temnospondyls in South America has been greatly
expanded in the last 10 years, increasing their overall significance. They
occur in Argentina, Brazil and Uruguay, and range from the Guadalupian to the
Late Triassic. The Early Triassic temnospondyl record in southern Brazil is
mainly composed of fragmentary specimens, usually represented by dermal skull
bones from the Sanga do Cabral Formation. Some of these fragments were
tentatively referred to Lydekkerinidae and Rhytidosteidae based on their
characteristic ridge-grooved âspider-webâ pattern of ornamentation. In this
contribution we report, for the first time, a temnospondyl skull fragment with
pustulated sculpturing pattern, which is tentatively ascribed to
Plagiosauridae. This new record could indicate the presence of a new
temnospondyl taxon for the Lower Triassic of South America.
Furtado Cabreira, S., and Cisneros, J.C. 2009. Tooth histology of the
parareptile Soturnia caliodon from the Upper Triassic of Rio Grande do Sul,
Brazil. Acta Palaeontologica Polonica.
ABSTRACT: A histological analysis of the dentition of the small procolophonid
parareptile Soturnia caliodon reveals detailed information concerning tooth
implantation and replacement for this taxon. The presence of acrodont tooth
implantation is verified, which contradicts current models for procolophonid
dentition. A heterogeneous enamel layer, that reaches large thickness on the
cusps, and a broad secondary dentine are also recorded. These structures
provide a very stable occlusal morphology that extends the useful life of the
teeth. During the process of replacement, old teeth were not pushed out but
reabsorbed. The evidence indicates that Soturnia caliodon had a very low rate
of tooth replacement which constitutes a valuable adaptation for its high-fibre
Tantawy, A.A.A., Keller, G., and Pardo, A. 2009. Late Maastrichtian volcanism
in the Indian Ocean: effects on calcareous nannofossils and planktic
Foraminifera. Palaeogeography, Palaeoclimatology, Palaeoecology 284(1-2):63-87.
ABSTRACT: The biotic effects of volcanism have long been the unknown factors in
creating biotic stress, and the contribution of the Deccan volcanism to the KâT
mass extinction remains largely unknown. Detailed studies of the volcanic-rich
sediments of Indian Ocean Ninetyeast Ridge Sites 216 and 217 and Wharton Basin
Site 212 reveal that the biotic effects of late Maastrichtian volcanism on
planktic foraminifera and calcareous nannofossils are locally as severe as
those of the KâT mass extinction. The biotic expressions of these high stress
environments are characterized by the Lilliput effect, which includes reduced
diversity by eliminating most K-strategy species, and reduction in specimen
size (dwarfing), frequently to less than half their normal adult size of both
r-strategy and surviving K-strategy species. In planktic foraminifera, the most
extreme biotic stress results are nearly monospecific assemblages dominated by
the disaster opportunist Guembelitria, similar to the aftermath of the KâT mass
extinction. The first stage of improving environmental conditions results in
dominance of dwarfed low oxygen tolerant Heterohelix species and the presence
of a few small r-strategy species (Hedbergella, Globigerinelloides). Calcareous
nannofossil assemblages show similar biotic stress signals with the dominance
of Micula decussata, the disaster opportunist, and size reduction in the mean
length of subordinate r-strategy species particularly in Arkhangelskiella
cymbiformis and Watznaueria barnesiae. These impoverished and dwarfed late
Maastrichtian assemblages appear to be the direct consequences of mantle plume
volcanism and associated environmental changes, including high nutrient influx
leading to eutrophic and mesotrophic waters, low oxygen in the water column and
decreased watermass stratification.
Xing, L., Ye, Y., Shu, C., Peng, G., and You, H. 2009. Structure, orientation
and finite element analysis of the tail club of Mamenchisaurus hochuanensis.
Acta Geologica Sinica (English Edition) 83(6):1031-1040.
ABSTRACT: The structure and orientation of the posterior extremity (tail club)
of the caudal vertebrae of Mamenchisaurus hochuanensis Young and Chao, 1972
from the Upper Jurassic Shangshaximiao Formation has been analyzed to determine
the tail club function using Finite Element Analysis. Of the four caudal
vertebrae composing the tail club, the second largest (C"1") was probably the
most proximal, and is fixed with the preceding sequence of the caudal
vertebrae, whereas the smallest (C"4") is free and forms the termination of the
tail club. Our analysis also suggests that the tail club is more efficient in
lateral swinging rather than up-and-down motion, and that the best region for
the tail club to impact is at the spine of the largest of the four caudals
(C"2"), with a maximum load for impact at about 450 N. The tail club of
Mamenchisaurus hochuanensis probably also had limitations as a defense weapon
and was more possibly a sensory organ to improve nerve conduction velocity to
enhance the capacity for sensory perception of its surroundings.
Benson, R.B.J., Butler, R.J., Lindgren, J., and Smith, A.S. 2009. Mesozoic
marine tetrapod diversity: mass extinctions and temporal heterogeneity in
geological megabiases affecting vertebrates. Proceedings of the Royal Society
B: Biological Sciences. doi: 10.1098/rspb.2009.1845.
ABSTRACT: The fossil record is our only direct means for evaluating shifts in
biodiversity through Earth's history. However, analyses of fossil marine
invertebrates have demonstrated that geological megabiases profoundly influence
fossil preservation and discovery, obscuring true diversity signals. Comparable
studies of vertebrate palaeodiversity patterns remain in their infancy. A new
species-level dataset of Mesozoic marine tetrapod occurrences was compared with
a proxy for temporal variation in the volume and facies diversity of
fossiliferous rock (number of marine fossiliferous formations: FMF). A strong
correlation between taxic diversity and FMF is present during the Cretaceous.
Weak or no correlation of Jurassic data suggests a qualitatively different
sampling regime resulting from five apparent peaks in TriassicâJurassic
diversity. These correspond to a small number of European formations that have
been the subject of intensive collecting, and represent âLagerstÃtten effectsâ.
Consideration of sampling biases allows re-evaluation of proposed mass
extinction events. Marine tetrapod diversity declined during the Carnian or
Norian. However, the proposed end-Triassic extinction event cannot be
recognized with confidence. Some evidence supports an extinction event near the
Jurassic/Cretaceous boundary, but the proposed end-Cenomanian extinction is
probably an artefact of poor sampling. Marine tetrapod diversity underwent a
long-term decline prior to the CretaceousâPalaeogene extinction.
Jerry D. Harris
Director of Paleontology
Dixie State College
225 South 700 East
St. George, UT 84770 USA
Phone: (435) 652-7758
Fax: (435) 656-4022
"The optimist thinks this is the best
of all possible worlds. The pessimist
fears it is true."
-- J. Robert Oppenheimer
"In nuclear war all men are cremated
-- Dexter Gordon