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New Papers the 13th
Voigt, S., Buchwitz, M., Fischer, J., Krause, D., and Georgi, R. 2008.
Feather-like development of Triassic diapsid skin appendages.
Naturwissenschaften. doi: 10.1007/s00114-008-0453-1.
ABSTRACT: Of the recent sauropsid skin appendage types, only feathers
develop from a cylindrical epidermal invagination, the follicle, and show
hierarchical branching. Fossilized integuments of Mesozoic diapsids have
been interpreted as follicular and potential feather homologues, an idea
particularly controversially discussed for the elongate dorsal skin
projections of the small diapsid Longisquama insignis from the Triassic of
Kyrgyzstan. Based on new finds and their comparison with the type material,
we show that Longisquama's appendages consist of a single-branched internal
frame enclosed by a flexible outer membrane. Not supporting a categorization
either as feathers or as scales, our analysis demonstrates that the
Longisquama appendages formed in a two-stage, feather-like developmental
process, representing an unusual early example for the evolutionary
plasticity of sauropsid integument.
Mannion, P.D. 2008. A rebbachisaurid sauropod from the Lower Cretaceous of
the Isle of Wight, England. Cretaceous Research. doi:
ABSTRACT: Rebbachisauridae is one of the most enigmatic and poorly
understood clades of sauropod dinosaurs. They are considered to be basal
diplodocoids, are known solely from the Cretaceous (Hauterivian-Coniacian),
and have only been recovered from Africa, South America, and Europe. As a
result of their extreme skeletal reduction, rebbachisaurid material is
highly susceptible to destructive taphonomic processes and thus most
remains are highly incomplete and fragmentary. Previous remains attributed
to rebbachisaurids from England are restricted to isolated teeth. Here a
sauropod scapula from the Lower Cretaceous (Barremian) Wessex Formation of
the Isle of Wight, England, is described. Although incomplete, this scapula
possesses both the extreme dorsoventral expansion of the scapular blade and
the "hook"-like acromial process that are characteristic of rebbachisaurids.
This study has also enabled the recognition of a putative local synapomorphy
of Rebbachisauridae, with the highest point on the dorsal margin of the
scapula blade equal to or exceeding that of the dorsal margin of the
proximal plate. This scapula is one of the oldest known examples of a
rebbachisaurid and represents the first postcranial remains of this clade to
be described from the United Kingdom. In addition, it provides further
support for the presence of rebbachisaurids in the Early-mid Cretaceous of
Li, G., Chen, P., Wang, D., and Batten, D.J. 2008. The spinicaudatan
Tylestheria and biostratigraphic significance for the age of dinosaur eggs
in the Upper Cretaceous Majiacun Formation, Xixia Basin, Henan Province,
China. Cretaceous Research. doi: 10.1016/j.cretres.2008.09.002.
ABSTRACT: The spinicaudatan Tylestheria was first described from the clam
shrimp ("conchostracan") Halysestheria yui Zone in the upper Turonian First
Member of the Nenjiang Formation, which crops out in the Songliao Basin in
Heilongjiang and Jilin provinces, north-east China. Representatives of the
genus have been found previously only in this basin. The species described
herein as Tylestheria xixiaensis sp. nov. was recovered from the
dinosaur-egg-bearing Majiacun Formation in the Xixia Basin, south-west Henan
Province. The age of this formation has been uncertain hitherto, with both
Early and Late Cretaceous determinations having been made. The recovery of
T. xixiaensis from it suggests that the fossil bearing strata can be
correlated with the First Member of the Nenjiang Formation and are,
therefore, also of Turonian age.
Santucci, R.M. 2008. First titanosaur (Saurischia, Sauropoda) axial remains
from the Uberaba Formation, Upper Cretaceous, Bauru Group, Brazil.
Historical Biology. doi: 10.1080/08912960802461033.
ABSTRACT: The Adamantina and Marılia formations are considered to be the
richest vertebrate-bearing units in the Bauru Group, Upper Cretaceous,
Brazil. In contrast, the fossil content from the Uberaba Formation, which
only outcrops in Minas Gerais State, is scarce and poorly understood. In
this essay the first taxonomically informative titanosaur remains unearthed
from this unit are reported. They comprise anterior caudal vertebrae from
two different individuals corresponding to a probably basal titanosaur
(CPP-360) and a derived titanosaur (CPP-217). Although these remains can be
clearly distinguished from other titanosaurs on the basis of their unique
association of characteristics like the presence of mildly procoelous
centra, lateral pits in the anterior caudal vertebrae, and prezygapophyses
with a dorsal protuberance in presence of strongly developed prespinal,
spinopostzygapophyseal and centropostzygapophyseal laminae in CPP-217, more
complete materials are needed to propose them new names.
Andrade, M.B.d., and Bertini, R.J. 2008. A new Sphagesaurus
(Mesoeucrocodylia: Notosuchia) from the Upper Cretaceous of Monte Alto City
(Bauru Group, Brazil), and a revision of the Spagesauridae. Historical
Biology 20(2): 101-136. doi: 10.1080/08912960701642949.
ABSTRACT: Since the description of Sphagesaurus, mostly dental material has
been reported, apart from two incomplete skulls. Here we describe a new
species of Sphagesaurus, from Monte Alto City, Southeastern Brazil, which
includes the skull and most of the mandible. Distinctive characters (e.g.
antorbital fenestra; robust quadrate; anterior mandibular teeth incisiform;
ornamented sulcate palate) allow differentiation from S. huenei. Several
characters allow assignment to the genus Sphagesaurus (e.g. teardrop-like
oblique molariform teeth), while new information is provided (e.g.
premaxilla, pterygoid and mandible morphology; jugal foramen; occipital
surface; battery of mandibular teeth). A revision of the Family
Sphagesauridae Kuhn 1968 is given. A preliminary phylogenetic analysis
supports a sister-taxon relationship for S. huenei and the new species. The
phylogenetic relationship of notosuchians is explored. Sphagesaurids were
terrestrial notosuchians that evolved during the Upper Cretaceous of South
America, known only from the Adamantina Formation, Campanian-Maastrichtian
(Upper Cretaceous) from Brazil.
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
"I have made this letter longer
than usual because I lack the
time to make it shorter."
-- Blaise Pascal