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Willie Wonka and the New Papers
Dentzien-Dias, P.C., Schultz, C.L., and Bertoni-Machado, C. 2008. Taphononmy
and paleoecology inferences of vertebrate ichnofossils from Guará Formation
(Upper Jurassic), southern Brazil. Journal of South American Earth Sciences
25(2):196-202. doi: 10.1016/j.jsames.2007.08.008.
ABSTRACT: In southern Brazil, the eolian facies of the Guará Formation (Late
Jurassic) reveal footprints and trackways of vertebrates (dinosaurs), as
well as burrows made by small vertebrates. All the footprints and trackways
are preserved in dunes and sand sheets. The footprints made in the sand
sheets are not well preserved due to intense trampling and can be
distinguished only by the deformation of the sandstone laminations. In some
cases it is possible to see this deformation in plan and in section. Tracks
of theropods, ornithopods and middle-sized sauropods are present. Two
footprints preserved in the foreset of a paleodune permitted recognition of
slide structures and identification of the trackmaker, a theropod. Burrows
horizontally across the foresets were found at this same paleodune. Ribbons
of massive sandstone ? interpreted as the partial filling of the base of the
burrows ? covered by little blocks of stratified sandstone ? suggest the
collapse of the burrow roof inward. There are no body fossils in the Guará
Formation, consequently the preservation of these tracks provides unique
evidence of widespread dinosaurs activity in southern Brazil near the end of
Diedrich, C. 2008. Millions of reptile tracks?Early to Middle Triassic
carbonate tidal flat migration bridges of Central Europe?reptile immigration
into the Germanic Basin. Palaeogeography, Palaeoclimatology, Palaeoecology
259(4):410-423. doi: 10.1016/j.palaeo.2007.09.019.
ABSTRACT: Discoveries of vertebrate track sites in Central Europe have
occurred in 75 localities in carbonate tidal flats of the Middle Triassic.
In the Germanic Basin carbonate tidal flats were wide-span mapped, resulting
in the finding of millions of small- to medium-sized reptile tracks. In the
west of the basin the sediment of the Lower Muschelkalk to basal Upper
Muschelkalk contains at least 21 track horizons, whereas in the eastern part
more typically marine conditions were present. Here, tidal flats with
additional track beds started earlier during the Upper Bunter and
demonstrated marine ingression from the eastern Silesian gate. During low
stands these tidal flats comprised inter-peninsula bridges, which allowed
migration of reptiles. Only two medium to small prolacertilian reptiles,
which were fully adapted to these environments, left any kind of track. A
large thecodont reptile such as Euparkeria was the potential predator that
may rarely have hunted the main small trackmakers Macrocnemus and
Jouve, S., Bouya, B., and Amaghzaz, M. 2008. A long-snouted dyrosaurid
(Crocodyliformes, Mesoeucrocodylia) from the Paleocene of Morocco:
phylogenetic and palaoebiogeographic implications. Palaeontology
51(2):281-294. doi: 10.1111/j.1475-4983.2007.00747.x.
ABSTRACT: New material of a long-snouted dyrosaurid has been discovered in
the Paleocene of Morocco. It consists of a well-preserved skull with
embedded mandible and four dorsal vertebrae. The particularly elongate
snout, proportionally the longest of all known dyrosaurids, allows precise
identification of this material as Atlantosuchus coupatezi Buffetaut, 1979a,
and presentation of an emended diagnosis for this species previously known
only from a mandibular symphysis. A phylogenetic analysis of the dyrosaurids
indicates a close relationship between A. coupatezi and Rhabdognathus. It
also confirms a previous hypothesis that Congosaurus is distinct from
Hyposaurus. It is more closely related to Atlantosuchus than Hyposaurus. The
analysis also allows palaeobiogeographic interpretations to be made.
Dyrosaurids ranged from North Africa to other areas. They were rare during
the Maastrichtian and endemic to each continent at this time. Competition
with large marine reptiles, such as mosasaurs, limited their dispersal
during the Late Cretaceous. The disappearance of these rivals during the
?K-T crisis? enabled their diversification and widespread dispersal during
the Paleocene, with the same genera present on several continents.
Benson, R.B.J., Barrett, P.M., Powell, H.P., and Norman, D.B. 2008. The
taxonomic status of Megalosaurus bucklandii (Dinosauria, Theropoda) from the
Middle Jurassic of Oxfordshire, UK. Palaeontology 51(2):419-424. doi:
ABSTRACT: The lectotype of the Middle Jurassic theropod dinosaur
Megalosaurus bucklandii, a right dentary, can be diagnosed on the basis of
two unique characters: a longitudinal groove on the ventral part of the
lateral surface of the dentary and a slit-like anterior Meckelian foramen.
This taxon, the first dinosaur to be scientifically described, is therefore
valid. Currently, however, no further material can be referred to this
species with any certainty. Megalosaurus bucklandii occupies an uncertain
systematic position but is not an abelisaurid or coelophysoid. Additionally,
it does not possess the diagnostic dentary characters that are present in
all known spinosauroids. Owing to this uncertainty, use of the family
Megalosauridae should be discontinued until such time as its systematic
position becomes clearer.
Averianov, A.O., Martin, T., Skutschas, P.P., Rezvyi, A.S., and Bakirov,
A.A. 2008. Amphibians from the Middle Jurassic Balabansai Svita in the
Fergana Depression, Kyrgystan (central Asia). Palaeontology 51(2):471-485.
ABSTRACT: Larval and metamorphosed Ferganobatrachus riabinini
(Temnospondyli, Brachyopoidea), metamorphosed Kokartus honorarius (Caudata,
Karauridae), an indeterminated karaurid (Karauridae indet.) and, presumably,
anurans (?Anura indet.) are represented by isolated cranial and postcranial
skeletal elements in the Middle Jurassic (Bathonian?Callovian) Balabansai
Svita of the Fergana Depression, Kyrgyzstan. The Balabansai vertebrate
assemblage is one of the few faunas in which non-lissamphibian
temnospondyls, stem caudates and anurans occur together. The presence of a
supraglenoid foramen and a complex strap-like glenoid on the scapulocoracoid
in Kokartus supports its basal phylogenetic position within the Caudata.
Evans, S.E., and Manabe, M. 2008. An early herbivorous lizard from the Lower
Cretaceous of Japan. Palaeontology 51(2):487-498. doi:
ABSTRACT: The Lower Cretaceous Tetori Group of Japan has yielded diverse
freshwater and terrestrial vertebrate assemblages. The most productive small
vertebrate locality is the ?Kaseki-Kabe? or ?fossil-bluff? at Kuwajima,
Hakusan City, Ishikawa Prefecture. These deposits have produced at least six
distinct lizard taxa of which one, described and named here as Kuwajimalla
kagaensis, has lanceolate denticulate teeth convergent on those of the
living Iguana. This type of dentition is rare among living lizards and is
usually considered indicative of herbivory and, more specifically, folivory.
Kuwajimalla kagaensis provides the earliest unambiguous record of squamate
herbivory. Comparisons with modern and fossil lizards suggest that
Kuwajimalla may be an early relative of the macrocephalosaurines, a group of
large herbivores well represented in the Upper Cretaceous of Mongolia.
Mayr, G. 2008. Phylogenetic affinities of the enigmatic avian taxon
Zygodactylus based on new material from the early Oligocene of France.
Journal of Systematic Palaeontology. doi: 10.1017/S1477201907002398.
ABSTRACT: Until now, the avian taxon Zygodactylus has been known only from
distal tibiotarsi and tarsometatarsi from the early Miocene of Europe.
Although the tarsometatarsus exhibits derived similarities to that of extant
Pici (barbets, toucans, woodpeckers and their allies), it differs in many
aspects and the phylogenetic affinities of Zygodactylus were uncertain.
Here, a well-preserved skeleton with a tentatively referred skull is
described from the early Oligocene of the Luberon, southern France, as a new
species, Z. luberonensis. It is about 10 million years older than previously
assigned species and exhibits derived characters which support a clade
comprising Zygodactylus and Eocene zygodactyl birds that were assigned to
the taxon ?Primoscenidae?. Primoscenidae Harrison & Walker, 1977 is
synonymised with Zygodactylidae Brodkorb, 1971. Zygodactylus lacks derived
features of crown group Piciformes and the derived similarities in the
distal tarsometatarsi of Zygodactylus and the Pici are thus a striking
example of convergence. Instead, the analysis results in a sister group
relationship between Zygodactylidae and Passeriformes (passerines), and
morphological characters are listed which support this hypothesis.
Recognition of Zygodactylidae as the possible sister taxon of the
Passeriformes implies that stem group representatives of passerines already
existed by the early Eocene.
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
"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
--- Demetri Martin