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Langobardisaurus & Gobekko papers
From: Ben Creisler
A number of recent non-dino papers:
Franco Saller, Silvio Renesto & Fabio M.Dalla Vecchia (2013)
First record of Langobardisaurus (Diapsida, Protorosauria) from the
Norian (Late Triassic) of Austria, and a revision of the genus.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 268(1): 83-95
A new specimen of the small protorosaurian reptile Langobardisaurus
pandolfii is described. It was collected from the Seefeld Formation,
of Late Triassic (Norian) age, in the Innsbruck area (Austria) and
represents the first occurrence of Langobardisaurus outside Italy.
Although preserved mostly as an impression, the find is significant
because it extends the palaeogeographic range of the genus and it is
the second specimen known to date with the skull fully exposed. The
preserved portions of the limb elements show that the bones are
hollow, with a layer of compacta and without any trace of spongiosa.
Reappraisal of all the specimens assigned to the genus
Langobardisaurus reveals no significant differences between L.
pandolfii and L. tonelloi, allowing to consider the latter as a junior
synonym of the former.
Juan D. Daza, Aaron M. Bauer & Eric Snively (2013)
Gobekko cretacicus (Reptilia: Squamata) and its bearing on the
interpretation of gekkotan affinities.
Zoological Journal of the Linnean Society 167(3): 430–448
Gobekko cretacicus, a Cretaceous lizard from the Gobi Desert of
Mongolia, is a key fossil for understanding gecko phylogeny. We
revisit this fossil using high-resolution X-ray computed tomography.
The application of this imaging method reveals new information about
sutures, bone shape, and structural details of the palate and
basicranium. These data were used to assess the phylogenetic
affinities of Gobekko in the context of an existing squamate data set.
The effects of character ordering, search strategy, and the addition
of another putative gekkonomorph (Hoburogekko suchanovi) on inferred
gekkonomorph relationships were explored. Available specimens of G.
cretacicus are skeletally mature but have unfused nasals, frontals,
and parietals, and (possibly) a persistent basicranial fenestra. Some
putative gekkonomorphs are not consistently supported as closer to
crown clade gekkotans than to autarchoglossans. In a strict consensus
both Gobekko and Hoburogekko form a polytomy with extant geckos. Some
of the adult character states of Gobekko are observable in embryos of
extant species. The evolution of tubular frontals and dentaries in
gekkotans may be structurally related to the loss of the postorbital
and supratemporal bars in this lineage. The complete lack of a
parietal foramen, and presumably a light-sensitive parietal eye, in
this clade is of interest and could indicate an early origin of
nocturnality in geckos.
Also, for the trace fossils:
Sidney R. Ash & Stephen T. Hasiotis (2013)
New occurrences of the controversial Late Triassic plant fossil
Sanmiguelia Brown and associated ichnofossils in the Chinle Formation
of Arizona and Utah, USA.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 268(1): 65-82
Fragments of the rare and distinctive palm-like leaves of the
controversial Late Triassic plant Sanmiguelia have been discovered
recently in both Petrified Forest National Park, Arizona and Arches
National Park, Utah. Although, the new specimens do not clarify the
classification of this intriguing fossil, they do confirm that it
occurs in all members of the Chinle Formation except for the very
lowest units, the Shinarump, Mesa Redondo, and Temple Mountain
members. Furthermore, their discovery in Petrified Forest National
Park extends the known geographical distribution of the fossil into
east-central Arizona and demonstrates that it is a characteristic
member of the Late Triassic flora of the American southwest and
requires a revision of the Chinle floral zone scheme proposed and
revised earlier by Ash (1980). In Petrified Forest National Park the
leaves are associated with several types of ichnofossils including
Scoyenia, Arenicolites, Cylindrichum, cf. Scolicia, cf. Beaconites,
Selenchnites, and other trace fossils in open nomenclature. These
trace fossils suggest that Sanmiguelia was preserved in high moisture,
imperfectly drained, water-margin setting inhabited by phytosaurs,
snails, horseshoe crabs, and a variety of arthropods such as beetles
and dipteran larvae and record high water table conditions punctuated
by flooding and overbank deposition. The findings reported here
generally support and improve on previous interpretations of the
paleoenvironment inhabited by the Sanmiguelia plant.