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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 
herbivorous niche.

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. 
doi: 10.1016/j.palaeo.2009.08.025.

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
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

"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