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New Papers of a Wimpy Kid

ânot a slight on any of these authors, I assure you!...

Grigorescu, D., Garcia, G., Csiki, Z., Codrea, V., and Bojar, A.-V. 2010. 
Uppermost Cretaceous megaloolithid eggs from the HaÅeg Basin, Romania, 
associated with hadrosaur hatchlings: search for explanation. Palaeogeography, 
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2010.03.031.

ABSTRACT: Four localities in the Upper Cretaceous (Maastrichtian) of the HaÅeg 
Basin (in order of discovery, TuÅtea, ToteÅti-baraj, NÄlaÅ-Vad and Livezi) have 
yielded clutches of megaloolithid eggs. Egg morphology and size, eggshell 
thickness, external ornamentation and internal microstructure, pore density and 
geometry, as well as morphology of the clutches (where this could be observed) 
are all similar among the four localities, allowing the assignment of the eggs 
to Megaloolithus cf. siruguei. Most egg occurrences are related to paleosols of 
variable chemical composition and maturity, developed within different parts of 
the floodplain.
     The nesting horizon from TuÅtea was partially reconstructed on a 160 m2 
surface, allowing a thorough analysis of the taphonomy of the eggs and 
clutches. It has also yielded hatchling remains at different ontogenetic 
developmental stages, and even, more rarely, embryo remains as well. The bones 
occur in the vicinity of or even within the clutches; in a single case, 
incompletely ossified embryonic skeletal remains, including a dentary tooth, 
were found inside an incomplete egg. Without exception, the neonate remains 
belong to the basal hadrosaurid Telmatosaurus transsylvanicus, one of the 
common dinosaur species in the faunal assemblage. No sauropod neonate remains 
were found in the nesting horizon from TuÅtea; only a fragmentary pelvic girdle 
and caudal vertebrae of an adult titanosaurian were unearthed recently 20 cm 
above the nesting horizon. None of the other three megaloolithid localities in 
the HaÅeg Basin provided neonatal remains of any dinosaur species.
     Despite the general consensus that the Megaloolithus oogenus belongs 
exclusively to titanosaurian sauropods, the co-occurrence of megaloolithid eggs 
and hadrosaurid neonatal remains at TuÅtea seems to contradict this view. 
Previous cladistic analyses of dinosauroid ootaxa might offer an explanation of 
this controversial issue. These analyses have revealed that Megaloolithidae 
appears to be the sister-group of Spheroolithidae, usually regarded as a 
hadrosaurid egg family. Perhaps a significant amount of homoplasy is present in 
the evolution of dinosaurian eggs, whose structure depends on incubation 
environment as well as biology and physiology of the reproductive system 
itself, and that the oospecies of Megaloolithus might have been laid by 
different higher-level taxa, including both titanosaurian sauropods and (basal) 
hadrosaurids. Understanding the significance of this paraphyletic distribution 
requires further study.

Prauss, M.L. 2010. Marine palynology of upper Maastrichtian to lowermost Danian 
strata from the Mullinax-1 core, Brazos River, Texas, USA, â evidence for 
palaeoenvironmental changes. Palaeogeography, Palaeoclimatology, Palaeoecology. 
doi: 10.1016/j.palaeo.2010.03.035.

ABSTRACT: The quantitative marine palynology of a 25.36 m long upper 
Maastrichtian to lower Danian core from Brazos, Texas, is compared and 
integrated with planktonic foraminiferal stratigraphy and, in the upper part, 
with stable oxygen and carbon isotopes from benthic foraminifera. The K/Pg 
boundary, defined by the base of planktonic foraminiferal zone P0 and the onset 
of a negative Î13C shift, closely corresponds to the appearance of lowermost 
Danian organic-walled dinocysts. Based on various palynological proxies as well 
as on sedimentologic features, a sequence stratigraphic subdivision of the 
section is proposed. Accordingly, from the base to the top, a second order 
relative sea-level rise is inferred, modified by several third order cycles. 
The most prominent change in dinocyst assemblages is related to a major 
transgression pulse at about 18.50 m core depth. The so-called "event deposit" 
(ED), a siliciclastic unit located about 97 cm below the base of the P0 
foraminifera zone in the present section, possibly represents a combination of 
episodic relative sea-level low and lag deposit due to initial transgression. 
Between the base of the ED and the K/Pg boundary, the gradual increase to peak 
abundance of trilete spores renders a redeposition of this intervening 
sedimentary unit improbable and demonstrates a significant time lag between 
these two horizons. Throughout the section, significant fluctuations of both 
oxygen- and carbon isotopes are present. Suggested warm episodes correlate with 
increased dinocyst proportions indicative of open neritic, warm-temperate 
surface waters, whereas cool episodes largely correlate to an increase of the 
tropical-subtropical dinocyst fraction. This correlation is considered 
primarily a function of relative sea-level change, restricting surface water 
circulation largely to the subtropics during sea-level lows and cooler climates 
and vice versa. In addition, cool climates largely correlate to heavier Î13C 
values and an increased ratio of peridinioid to gonyaulacoid!
suggestive of significant fluctuations in marine primary productivity preceding 
the K/Pg boundary. By contrast, the lower Danian is characterised by the onset 
of both persistent warm conditions and a drawdown of marine primary 
productivity. These data suggest that prominent, high frequency 
palaeoenvironmental changes precede the K/Pg boundary, which is inconsistent 
with a single "catastrophic" impact as the cause for the K/Pg boundary event. 
However, according to the onset and distinct distribution of the peak abundance 
of trilete spores, the base of the ED may actually reflect the Chicxulub 
impact, which probably contributed significantly to K/Pg boundary crisis within 
the biosphere. By contrast, no significant changes within palynologic proxies 
are observed across the time equivalent of a yellow clay horizon recently 
discovered from a single outcrop at Brazos, which has been suggested as the 
actual Chicxulub impact fallout.

Hone, D.W.E., Choiniere, J., Sullivan, C., Xu, X., Pittman, M., and Tan, Q. 
2010. New evidence for a trophic relationship between the dinosaurs 
Velociraptor  and Protoceratops. Palaeogeography, Palaeoclimatology, 
Palaeoecology. doi: 10.1016/j.palaeo.2010.03.028.

ABSTRACT: Reconstructing the palaeoecology of extinct tetrapods is fraught with 
difficulties. Fossilized evidence of direct trophic interactions between 
tetrapods is rare, whether the interactions involve predation or scavenging. 
Typically this evidence is limited to preserved stomach contents or bite marks 
on bones (when they can be confidently attributed to specific taxa) that make 
it possible to begin to piece together the trophic webs that existed in ancient 
ecosystems. The dramatic âfighting dinosaursâ fossil of a Velociraptor 
preserved in combat with a Protoceratops  provides an outstanding, but still 
lone, example of the two taxa interacting. Here new evidence of a Velociraptor 
feeding on the carcass of a Protoceratops is presented, based on tooth-marked 
bones of the latter that were found in association with shed teeth of the 
former in Upper Cretaceous deposits at Bayan Mandahu, Inner Mongolia, China. In 
contrast to the case of the fighting dinosaurs, which seems to represent active 
predation by a Velociraptor, the tooth marks on the Bayan Mandahu material are 
inferred to have been produced during late-stage carcass consumption either 
during scavenging or following a group kill. Feeding by Velociraptor upon 
Protoceratops  was probably a relatively common occurrence.

Weishampel, D.B., Csiki, Z., Benton, M.J., Grigorescu, D., and Codrea, V. 2010. 
Palaeobiogeographic relationships of the HaÅeg biota â between isolation and 
innovation. Palaeogeography, Palaeoclimatology, Palaeoecology. doi: 

ABSTRACT: The biogeographic significance of the Late Cretaceous HaÅeg fauna is 
assessed using both faunal and phylogenetic analyses. Although extremely 
endemic at the species level, the HaÅeg fauna is part of a larger European 
palaeobioprovince compared to roughly contemporary (Campanian-Maastrichtian) 
terrestrial faunas elsewhere in Europe. Phylogenetic analyses of five HaÅeg 
taxa, calibrated by biostratigraphic occurrences provide evidence of long ghost 
lineages. The geographic distributions of kogaionids, Kallokibotion, 
Allodaposuchus, and Zalmoxes (together with their European sister taxa) may 
have arisen from vicariant events between western Europe and North America, 
while the distribution of Telmatosaurus is an example of European endemism of 
Asiamerican origin.
     While HaÅeg seems to have acted as a dead-end refugium for Kallokibotion 
and Telmatosaurus, other faunal members (and their immediate sister taxa) are 
not restricted to Transylvania, but known otherwise from localities across 
southern Europe. In addition, Transylvania may have acted as an evolutionary 
cradle for kogaionids.
     Transylvania and the other southern faunas of Europe may represent a 
distinct division of the Late Cretaceous European palaeobioprovince. A boundary 
between this Tethyan Europe and the more western and northern cratonic Europe 
suggests something like the Wallace Line in the Malay Archipelago, in which two 
distinct faunal provinces with separate histories within a much larger, 
seemingly uniform geographic region are separated by a narrow boundary.

Lingham-Soliar, T., and Glab, J. 2010. Dehydration: a mechanism for the 
preservation of fine detail in fossilised soft tissue of ancient terrestrial 
animals Palaeogeography, Palaeoclimatology, Palaeoecology. doi: 

ABSTRACT: Early mineralization is widely regarded as an important factor in 
exceptionally preserved soft tissue in the fossil record. However, there is a 
race against time between soft tissue destruction and the mineralization 
process. Dehydration of terrestrial animal carcasses may gain valuable time in 
that race. The decay of collagen, the dominant protein in most animals, is 
poorly understood and consequently difficult to assess in fossils because of 
complex changes following the death of an animal. We analysed the 
ultrastructure of collagen from decomposed dolphin, python and turtle tissue, 
which had subsequently been air-dried, using Scanning and Transmission Electron 
microscopy and Small Angle X-ray Scattering. Despite severe exposure of the 
dolphin tissue to decay and dehydration, many collagen fibres maintained their 
structural integrity, showing little degradation. Fibril shrinkage as indicated 
by the characteristic D-banding of collagen was quite small in all the 
dehydrated tissue studied compared to native tissue. Thus, with respect to the 
first stage of preservation the structural identity of the tissue is retained. 
However, the ephemeral benefits of dehydration must be transcribed to long-term 
geological survival -- usually by mineralization. This would require 
re-hydration of the tissue so that decay by bacteria and -- release of minerals 
occurs or the tissue is exposed to water-borne minerals that permeate the 
tissue. Re-hydrating the dehydrated tissue showed minimal structural loss. In 
nature seasonal dry periods may have a devastating effect on animals often 
accounting for mass mortalities and unlikelihood of mineralization at the time 
(either authigenic mineralization or permineralization). However, with the 
return of the seasonal summer rains and floodwaters often rich in minerals, 
re-hydration of the dried animal carcasses or parts may present, as we have 
shown, a viable second chance for mineralization and long term survival of 
informative tissue structure. Briefly mentioned in compa!
rison is 
survival compared to collagen.

de la Fuente, M., and FernÃndez, M.S. 2010. An unusual pattern of limb 
morphology in the Tithonian marine turtle Neusticemys neuquina from the Vaca 
Muerta Formation, NeuquÃn Basin, Argentina. Lethaia. doi: 

ABSTRACT: Here, we report an unusual pattern in the manus and pes morphology of 
the Tithonian marine turtle Neusticemys neuquina. We analyse the forelimbs of 
two previously known specimens and describe the hind limbs of two previously 
undescribed specimens. Neusticemys neuquina is characterized by a relative 
elongation of both the forelimb and hind limb, compared with stem Chelonoidea, 
as well as an elongation of the pedal digit V, achieved through the elongation 
of the bones, as well as a moderate hyperphalangy. The elongation of pedal 
digit V is the most striking feature of N. neuquina, a feature unknown in other 

Dumont, E.R. 2010. Bone density and the lightweight skeletons of birds. 
Proceedings of the Royal Society B: Biological Sciences. doi: 

ABSTRACT: The skeletons of birds are universally described as lightweight as a 
result of selection for minimizing the energy required for flight. From a 
functional perspective, the weight (mass) of an animal relative to its 
lift-generating surfaces is a key determinant of the metabolic cost of flight. 
The evolution of birds has been characterized by many weight-saving adaptations 
that are reflected in bone shape, many of which strengthen and stiffen the 
skeleton. Although largely unstudied in birds, the material properties of bone 
tissue can also contribute to bone strength and stiffness. In this study, I 
calculated the density of the cranium, humerus and femur in passerine birds, 
rodents and bats by measuring bone mass and volume using helium displacement. I 
found that, on average, these bones are densest in birds, followed closely by 
bats. As bone density increases, so do bone stiffness and strength. Both of 
these optimization criteria are used in the design of strong and stiff, but 
lightweight, manmade airframes. By analogy, increased bone density in birds and 
bats may reflect adaptations for maximizing bone strength and stiffness while 
minimizing bone mass and volume. These data suggest that both bone shape and 
the material properties of bone tissue have played important roles in the 
evolution of flight. They also reconcile the conundrum of how bird skeletons 
can appear to be thin and delicate, yet contribute just as much to total body 
mass as do the skeletons of terrestrial mammals. 

Berman, D.S., Henrici, A.C., Brezinski, D.K., and Kollar, A.D. 2010. A new 
trematopid amphibian (Temnospondyli: Dissorophoidea) from the Upper 
Pennsylvanian of western Pennsylvania: earliest record of terrestrial 
vertebrates responding to a warmer, drier climate. Annals of the Carnegie 
Museum 78(4):289-318.

ABSTRACT: Fedexia striegeli, a new genus and species of trematopid temnospondyl 
amphibian, is described on the basis of a single specimen that includes the 
greater portion of the skull and articulated portions of both mandibles and the 
atlas-axis complex. The holotype was collected from Upper Pennsylvanianâearly 
Virgilian strata assignable to the lower part of the Casselman Formation of the 
Conemaugh Group in western Pennsylvania. This is not only the first trematopid 
to be reported from the state of Pennsylvania, but also, in addition to 
Actiobates Eaton, 1973, and Anconastes Berman et al., 1987, only the third 
reported Late Pennsylvanian member of the family that otherwise has a greater 
Early Permian representation.
     A cladistic analysis of the Dissorophoidea was performed utilizing 
primarily cranial characters and only members of Amphibamidae, Trematopidae, 
and Dissorophidae that are well represented in this field of inquiry. This 
includes Ecolsonia Vaughn, 1969, whose relationships to the latter two families 
have been controversial. The resultant cladogram depicts: 1) Fedexia to be 
nested within a monophyletic Trematopidae as the sister taxon to the terminal 
dichotomy of Anconastes and Tambachia Sumida et al., 1998; 2) Trematopidae and 
Dissorophidae as forming monophyletic sister clades; and 3) Ecolsonia, 
Dissorophus Cope, 1895, and Broiliellus Williston, 1914, as forming an 
unresolved, terminal trichotomy within the dissorophid clade.
     Fedexia is representative of a wide variety of Late Pennsylvanian, 
medium-to-large amphibian and amniote tetrapods that record the earliest 
occurrence of vertebrates adapted to a terrestrial existence in North America. 
It is hypothesized that this biotic event was in response to the final stage of 
a long-term, global climatic trend toward drier conditions during the 
Pennsylvanian from perhumid to humid during the Early and Middle Pennsylvanian 
to dry subhumid or semiarid in the latest Virgilian. The lattermost climatic 
stage, which was also coincident with a marked retreat of the southern polar 
hemisphere glaciers during the late Paleozoic Ice Age, was followed by a strong 
and progressive reversal of the climate and an advance of the southern 
hemisphere glaciers to conditions characteristic of the earlier Pennsylvanian.
     Climatic changes during the Pennsylvanian are chronicled not only by major 
changes in rock types and associated lithologies, but also by a shift in the 
biology of the vertebrates they preserve. Middle Pennsylvanian vertebrates are 
characterized by large, diverse assemblages of predominantly small, aquatic 
amphibians and fish preserved in black shales and cannel coals associated with 
coal-forming and sapropelic fluvial sediments that developed in permanently 
wet, abandoned river channels. In contrast, the terrestrially adapted 
vertebrates of the MissourianâVirgilian Pennsylvanian are typically preserved 
in thin deposits of freshwater limestone or their closely associated paleosols 
that are interpreted as representing seasonally dry lake deposits. Yet, aquatic 
amphibians continue to be a major constituent of Late Pennsylvanian vertebrate 

Marsicano, C.A., Mancuso, A.C., Palma, R.M., and Krapovickas, V. 2010. Tetrapod 
tracks in a marginal lacustrine setting (Middle Triassic, Argentina): taphonomy 
and significance. Palaeogeography, Palaeoclimatology, Palaeoecology. doi: 

ABSTRACT: Fossil tetrapod footprints not only provide valuable information 
about trackmaker paleobiology but also to give insight into details of the 
depositional conditions of the substrate at the time of imprinting. Therefore, 
in the present study the mode of formation and taphonomy of footprints in 
different substrates was used to investigate the gait and walking dynamics of 
the trackmakers as well as a source of additional information on the 
environmental conditions of the track-bearing beds during imprinting.
     The analyzed section corresponds to thick Middle Triassic 
lacustrine/deltaic deposits of the Ischichuca/Los Rastros Formation 
(Ischigualasto-Villa UniÃn Basin) that crops out at the Quebrada de Ischichuca 
in northwestern Argentina. Part of the track-bearing surfaces correspond to the 
top of sandy distributary channel mouth bars in a distal delta front setting 
that were exposed along the lake margin during a lake level fall. Cross-cutting 
relationships observed among ripple-marks, the footprints, and invertebrate 
traces of a softground suite of the Scoyenia ichnofacies suggest an omission 
surface. Measured trackway orientations in the sandstones are perpendicular to 
the paleo-shoreline, with the animals coming and going along the exposed top of 
the bars, probably for drinking. Laterally, the distal delta front deposits 
interfinger with track-bearing wackestone beds of palustrine origin deposited 
in a restricted local embayment lateral to the delta influenced environment. 
Trackway orientations in the wackestones are, in contrast, consistent with the 
animals moving nearly parallel to the lake border, probably along a preferred 
route. Evidences of a relative high groundwater table at the time of imprinting 
in the track-bearing surfaces are revealed by the well developed rims of 
extruded sediment and collapsed digits in the studied tracks and the nearly 
absence of associated desiccation cracks on the same surfaces. Nevertheless, 
temporary emergence cannot be ruled out when paleosoil formation was probably 
promoted as can be observed in the microstructure of both sandstones and 
wackestones. Moreover, footprint preservation in the wackestones might have 
been enhanced by partial hardening of the trampled surface during subaerial 
exposure. Combining ichnofossil content and taphonomy with facies analysis we 
identified in the lower part of the Ischichuca/Los Rastros succession a 
relatively rapid withdrawal of the water basinward that was probably due to a 
forced regression during early rifting of basin evolut!
     Footprints can also provide valuable information about locomotion dynamics 
and trackmaker behavior. Thus, the sideways deformation observed in the studied 
footprints, attributed to basal archosaurs and putative basal dinosaurs, can be 
related to an outward rotation of the foot during the step cycle, a condition 
that might allied to the development of the parasagittal posture in 
Archosauria. Besides, the densely trampled surface described herein constitutes 
the first documented evidence of putative social behavior among therapsid 
dicynodonts, the most important group of herviborous animals in the early 
Mesozoic terrestrial ecosystems throughout Gondwana.

Preto, N., Kustatscher, E., and Wignall, P.B. 2010. Triassic climates -- state 
of the art and perspectives. Palaeogeography, Palaeoclimatology, Palaeoecology. 
doi: 10.1016/j.palaeo.2010.03.015.

ABSTRACT: The climate of the Triassic period was characterized by a non-zonal 
pattern, dictated by a strong global monsoon system with effects that are most 
evident in the Tethys realm. This strong monsoonal regime is related to the 
aggregation of the Pangaean supercontinent, which by Triassic time was already 
completed. Climate oscillations existed within this framework. The harsh 
hothouse climatic conditions that characterized the Late Permian, and perhaps 
precipitated the end-Permian mass extinction, were probably maintained during 
the Early Triassic and may account for the impoverished, but distinctive, 
faunal and floral Lower Triassic associations. Although metazoan reef builders 
were probably the most affected group, carbonate production remained high at 
least in the western Tethys realm. The Middle Triassic was characterised 
locally by humid episodes, although their geographical distribution has yet to 
be clarified. The Carnian Pluvial Event, marks an episode of increased rainfall 
documented worldwide, was the most distinctive climate change within the 
Triassic. Different hypotheses have been proposed for its causes: changes of 
atmospheric or ocean circulation driven by plate tectonics; a peak of the 
global monsoon due to maximum continent aggregation; or triggering by the 
eruption of a large igneous province. Subsequently, the late Carnian and Norian 
seem to have been climatically stable, although minor climatic changes have 
recently been described even from this time period. Finally, the end Triassic 
extinction event is also associated with climate change, specifically warming 
and increased rainfall, but this evidence comes mostly from the northern parts 
of the Central Atlantic Magmatic Province, and the global pattern of climate 
change at the Triassic / Jurassic boundary has still to be resolved. Many 
facets of Triassic climate are intriguing and deserve further research. 
However, paleoclimate studies on the Triassic have so far been carried out only 
locally with different proxies. Those proxie!
s will re
inter-calibration, in order to depict correctly the temporal and geographical 
patterns of Triassic climate.

Gates, T.A., Sampson, S.D., Zanno, L.E., Roberts, E.M., Eaton, J.G., Nydam, 
R.L., Hutchison, J.H., Smith, J.A., Loewen, M.A., and Getty, M.A. 2010. 
Biogeography of terrestrial and freshwater vertebrates from the Late Cretaceous 
(Campanian) western interior of North America. Palaeogeography, 
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2010.03.008.

ABSTRACT: Previous biogeographic studies of Late Cretaceous (late Campanian) 
vertebrate faunas in the Western Interior Basin (WIB) of North America have 
suggested the presence of faunal and floral provincialism, characterized by 
distinct northern and southern âbiomes.â However, the âprovincialism 
hypothesisâ has been questioned based largely on the contention that the 
investigated faunas were recovered from a series of diachronous, 
time-transgressive deposits, and are therefore non-correlative.
     Extensive work in several fossiliferous units of late Campanian age, 
including the Dinosaur Park, Judith River, Two Medicine, Kaiparowits, 
Fruitland/Kirtland, and Aguja formations, has greatly increased understanding 
of WIB vertebrate faunas and their chronostratigraphic relationships. Here 
updated and greatly expanded faunal and chronostratigraphic data sets are 
utilized to undertake an extensive biogeographic analysis of these six 
terrestrial fossiliferous formations within the WIB of North America. 
Quantitative biogeographic comparisons of the formations and their constituent 
faunas are conducted using four statistical methods: analysis of similarity, 
Q-mode cluster analysis, parsimony analysis of endemicity, and correspondence 
     The results of this study provide strong support for highly divergent 
faunas in northern and southern regions of the WIB, with a latitudinal faunal 
gradient as an interface. Yet the nature of the interface between these faunas 
remains unclear, with possibilities including: 1) two or more discrete 
provinces separated by a zone (or zones) of faunal mixing; and 2) a continuous 
latitudinal gradient or cline, with no discrete zones of endemism. Lacking 
evidence of any physiographic barrier to north-south dispersal, climatic 
variation within the WIB is regarded as the most likely explanation for the 
overarching biogeographic patterns observed for late Campanian vertebrate taxa.

Evans, S.E., and Wang, Y. 2010. A new lizard (Reptilia: Squamata) with 
exquisite preservation of soft tissue from the Lower Cretaceous of Inner 
Mongolia, China. Journal of Systematic Palaeontology 8(1):81-95. doi: 

ABSTRACT: The Early Cretaceous Jehol Biota of China includes seven named lizard 
taxa: Yabeinosaurus tenuis and Dalinghosaurus longidigitus; the gliding 
Xianglong; more fragmentary remains referred to the genera Pachygenys and 
Mimobecklesisaurus; and the undiagnostic juvenile skeletons Jeholosaurus and 
Liaoningolacerta. Here we describe new lizard remains from the Yixian Formation 
at Liutiaogou, Ningcheng County, Inner Mongolia. The eight specimens vary in 
size and ontogenetic development, but appear to pertain to a single species. 
Several specimens show unparalleled preservation of soft tissue impressions 
including scalation and pigmentation, claw sheaths, sternal and extrastapedial 
cartilages, as well as rarely preserved skeletal elements like orbitosphenoids 
and postcloacal bones. The combination of characters precludes attribution to 
known taxa both within and outside China, and the new lizard is named 
Liushusaurus acanthocaudata gen. et sp. nov. Cladistic analysis supports the 
placement of Liushusaurus within the Scincogekkonomorpha, as the sister group 
of Scleroglossa. 

Brusatte, S.L., Benton, M.J., Desojo, J.B., and Langer, M.C. 2010. The 
higher-level phylogeny of Archosauria (Tetrapoda: Diapsida). Journal of 
Systematic Palaeontology 8(1):3-47.

ABSTRACT: Crown group Archosauria, which includes birds, dinosaurs, 
crocodylomorphs, and several extinct Mesozoic groups, is a primary division of 
the vertebrate tree of life. However, the higher-level phylogenetic 
relationships within Archosauria are poorly resolved and controversial, despite 
years of study. The phylogeny of crocodile-line archosaurs (Crurotarsi) is 
particularly contentious, and has been plagued by problematic taxon and 
character sampling. Recent discoveries and renewed focus on archosaur anatomy 
enable the compilation of a new dataset, which assimilates and standardizes 
character data pertinent to higher-level archosaur phylogeny, and is scored 
across the largest group of taxa yet analysed. This dataset includes 47 new 
characters (25% of total) and eight taxa that have yet to be included in an 
analysis, and total taxonomic sampling is more than twice that of any previous 
study. This analysis produces a well-resolved phylogeny, which recovers mostly 
traditional relationships within Avemetatarsalia, places Phytosauria as a basal 
crurotarsan clade, finds a close relationship between Aetosauria and 
Crocodylomorpha, and recovers a monophyletic Rauisuchia comprised of two major 
subclades. Support values are low, suggesting rampant homoplasy and missing 
data within Archosauria, but the phylogeny is highly congruent with 
stratigraphy. Comparison with alternative analyses identifies numerous scoring 
differences, but indicates that character sampling is the main source of 
incongruence. The phylogeny implies major missing lineages in the Early 
Triassic and may support a Carnian-Norian extinction event. 

Benson, R.B.J. 2010. The osteology of Magnosaurus nethercombensis (Dinosauria, 
Theropoda) from the Bajocian (Middle Jurassic) of the United Kingdom and a 
re-examination of the oldest records of tetanurans. Journal of Systematic 
Palaeontology 8(1):131-146.

ABSTRACT: Magnosaurus nethercombensis from the Lower Bajocian (Middle Jurassic) 
of Dorset, UK is a valid species, possessing a single autapomorphy: the 
presence of anteroposteriorly elongate foramina, inclined anterodorsally and 
located ventrally on the lateral surface of the dentary. It is the oldest known 
definite tetanuran dinosaur and shows two tetanuran features: a reduced ischial 
peduncle of the ilium and the presence of a marked femoral extensor groove. 
Other records of putative early tetanurans are reviewed: 'Zanclodon cambrensis' 
from the Rhaetian of Wales; remains from the Norian-Hettangian of Switzerland; 
Shuvosaurus and Protoavis from the Norian of Texas; Eshanosaurus from the 
Hettangian of China; theropod remains originally included in the syntype series 
of Scelidosaurus  from the Hettangian-Sinemurian of England; a fragmentary 
skeleton from the Sinemurian of Italy; Cryolophosaurus from the 
Sinemurian-Pliensbachian of Antarctica; the partial skeleton of a small 
theropod from the Toarcian of Morocco; and the lost syntype material of 
'Streptospondylus cuvieri' from the Toarcian of Whitby. None of these records 
can be confidently considered to be the earliest tetanuran record. An early 
Middle Jurassic age for the earliest-known tetanuran is more consistent with a 
restricted content of Ceratosauria, comprising Ceratosaurus, Elaphrosaurus, and 
abelisauroids, than with a wider content including coelophysoids, due to 
reduction in the length of phylogenetic ghost lineages. 

Modesto, S.P., and Botha-Brink, J. 2010. A burrow cast with Lystrosaurus 
skeletal remains from the Lower Triassic of South Africa. Palaios 25(4):274-281.

ABSTRACT: We report on a large burrow cast with skeletal contents from Lower 
Triassic strata of the Palingkloof Member of the Balfour Formation, which forms 
the lowermost portion of the Lystrosaurus Assemblage Zone (LAZ) of South 
Africa. The burrow cast is similar to large burrow casts previously described 
from the LAZ that were identified as large-scale Scoyenia domichnia. It is the 
first large burrow cast from the LAZ found to contain diagnostic fossil bone. 
The burrow cast is a relatively straight, subhorizontal (inclined 12Â), 
dorsoventrally compressed tube consisting of an entry ramp and living chamber; 
the entrance to the burrow is not preserved and there is no evidence that the 
ramp formed a spiral section. The skeletal material comprises a single, 
partial, disarticulated skeleton of a juvenile animal that can be assigned with 
confidence to the dicynodont genus Lystrosaurus. Whereas similar large-diameter 
burrow casts from strata slightly higher in the LAZ have been attributed to 
Lystrosaurus, we present an alternative hypothesis that a carnivorous tetrapod 
constructed the burrow. Our preferred hypothesis is supported by the 
observation that the interred Lystrosaurus  skeleton is too small to be the 
maker of this particular burrow, by the general observation that carnivorous 
tetrapods construct relatively straight burrows, and by the partial, 
disarticulated state of the skeleton, which we interpret as the remains of 
larded prey. We suggest that akidnognathid theriodonts of the genera 
Moschorhinus or Olivierosuchus, the most conspicuous large predators of the 
LAZ, were the constructors of large-diameter, subhorizontal burrows.

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

"I have noticed even people who
claim everything is predestined, and
that we can do nothing to change it,
look before they cross the road."

                   -- Stephen Hawking

"Prediction is very difficult,
especially of the future."

                   -- Niels Bohr