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Lamarqueavis, Cretaceous neornithine from 2010 and other not so recent overlooked papers

From: Ben Creisler

Many thanks to Vahe Demirjian from bringing Lamarqueavis Agnolin, 2010
to my attention. It's a good opportunity to cite some other papers
from the same open-access journal Studia Geologica Salmanticensia that
were not mentioned on the DML and dating back a few years.

Lamarqueavis Agnolin, 2010

Federico L. Agnolin (2010)
An avian coracoid from the Upper Cretaceous of Patagonia, Argentina.
Studia Geologica Salmanticensia 46 (2): 99–119

In the present paper, the new genus and species of neornithine bird,
Lamarqueavis australis is described. The specimen consists on an
isolated coracoid collected in Campanian-Maastrichtian beds of the
Allen Formation, at the Bajo Trapalcó fossiliferous locality, Río
Negro Province, Argentina. The specimen constitutes the first record
from South America of the neornithine clade Cimolopterygidae, a group
of modern-like birds that previously were known from Cretaceous and
Paleogene strata of North America, Europe, and Asia. The new genus
Lamarqueavis also includes previously described taxa, such as
“Cimolopteryx” minima and “C.” petra, from the Late Cretaceous of
North America. The new specimen fits well with the traditional
hypothesis that suggests that derived ornithurine birds were the
dominant taxa of shoreline and marine habitats during the Cretaceous,
whereas in inland environments basal taxa were more abundant. Finally,
on the basis of the meagre fossil neornithine record of the
Cretaceous, previous hypotheses concerning the place of cradle of
modern birds in Antarctica or North America are discussed.


Carlos Pascual-Arribas & Nieves Hernández-Medrano (2012)
Asociación de huellas de pterosaurio en el yacimiento de los Tormos
(Soria, España): implicaciones icnotaxonómicas. [Pterosaur tracks
association in “Los Tormos” tracksite (Soria, Spain): icnotaxonomic
Studia Geologica Salmanticensia 48 (1): 7-36

The Oncala Group of the Cameros Basin provides one of the largest
collections of pterosaur tracks in the world. 6 ichnospecies have been
defined so far, some of which coexist in the same tracksite. After
cleaning various levels of tracks from Los Tormos tracksite (Soria,
Spain), new tracks of these reptiles have been found belonging to four
different morphotypes at that same level, which do not correspond with
other two types of a lower level. The ichnites are assigned to two
well known ichnospecies (Pt. palacieisaenzi and Pt. cidacoi), two
others possibly could be assigned to already existing ichnospecies
(Pt. longispodus and Pt. nipponensis) and two morphotypes are
unidentified, one of which possibly belongs to a new ichnogenus and
ichnospecies. The simultaneity of different ichnospecies in the same
tracksite suggests that some of the various types of pterosaurs could
live in the same ecological niche, just as they do nowadays, for
example, a great diversity of birds in the Guadalquivir marshes
(Doñana National Park). The study of these tracks and their potential
trackmaker suggest that: a) The diagnosis of the ichnogenus
Pteraichnus should be amended because it reflects the general
description of all virtually existing pterosaur ichnites; b)
pterosaurs could move occasionally putting all their weight just on
their toes.


Carlos Pascual-Arribas & Nieves Hernández-Medrano (2011)
Posibles huellas de crías de terópodo en el yacimiento de
Valdehijuelos (Soria, España). [Possible baby theropod tracks at the
Valdehijuelos tracksite (Soria, Spain)]
Studia Geologica Salmanticensia  47(1): 77-110

The Valdehijuelos tracksite (Soria, Spain) has provided, in several
isolated plaques, a significant number of tiny theropod footprints,
between others with bigger size. The associated morphometric
characteristics and relationships make them different from those of
Grallator, Anchisauripus and Eubrontes ichnogenus, whose morphology is
relatively similar and whose size, in some cases (Grallator), is also
small. However, they appear to be quite similar to the big tracks
around so it could be supposed to be the baby of the big trackmakers.


Carlos Pascual-Arribas & Nieves Hernández-Medrano (2010)
Nuevos datos sobre el yacimiento icnítico de Las Cuestas I (Santa Cruz
de Yanguas, Soria, España). [New dates from Las Cuestas I tracksite
(Santa Cruz de Yanguas, Soria, España)]
Studia Geologica Salmanticensia  46(2): 123-157

Las Cuestas I tracksite is one of the largest in Oncala Group. Almost
600 theropod, ornithopod and sauropod dinosaur tracks can be
appreciated, as well as possible crocodile ones. Amongst them, the
most abundant ones are those belonging to sauropods, which are mostly
narrow trackway internal width, framed in the ichnogenus
Parabrontopodus and another new ichnogenus not defined yet. Ornithopod
footprints are related to Iguanodontipus ichnogenus, while those ones
of theropods are not related to any specific ichnogenus due to their
poor preservation. According to the findings, it is considered that
the place was frequented by sauropods belonging to Diplodocoidea
family and macronaria clade, by ornithopods of Camptosauridae family
or medium sized iguanodonthides and theropods members of
Megalosauridae and/or Ceratosauridae family.


Carlos Pascual-Arriba, Nieves Hernández-Medrano, Pedro
Latorre-Macarrón & Eugenio Sanz-Pérez (2009)
El icnogénero “Iguanodontipus” en el yacimiento de “Las Cuestas I”
(Santa Cruz de Yanguas, Soria, España) . [The Iguanodontipus
ichnogener in “Las Cuestas I” tracksite (Santa Cruz de Yanguas, Soria.
Studia Geologica Salmanticensia  45 (2): 105-128

Las Cuestas I (Soria, Spain) is one of the biggest tracksite in Oncala
Group. Until the moment, it has been catalogued almost 600,
ornithopod, theropod and mainly sauropod tracks.
The ornithopod tracks are similar to those used to define the
Iguanodontipus ichnogener (Sarjeant et al., 1998) from the Berriasian
in Dorset (England), that is why they are also included.
Very similar footprints to those described in this tracksite can be
seen a lot of tracksites in Oncala Group, both known and unknown.
They analysis of the potential trackmakers the tracks owners, reveals
that they could belong to the family of Camptosauridae (Camptosaurus,
Draconyx) or superfamily Iguanodontoidea, of small size.

An pre-print version of this paper came out last year but was not
mentioned here.  It's now officially published:

Kyle G. Rowe, Gregory M. Erickson, W. Gregory Sawyer & Brandon A. Krick (2014)
Evolution in Surfaces: Interaction of Topography with Contact Pressure
During Wear of Composites Including Dinosaur Dentition.
Tribology Letters 54(3): 249-255
DOI: 10.1007/s11249-013-0271-2

A two-parameter elastic foundation model is used to predict the
coupled evolution of contact pressure and wear of multicomponent
composite surfaces. The iterative model predicts the evolution of
surface shape for an initially flat multicomponent surface under
uniform applied pressure; where the components of the composite
surface are different materials of different wear rates. The model is
applied to elucidate the chewing surface morphology of the dentition
in a hadrosaurid dinosaur using wear rates measured from fossilized
dental tissues. Additionally, to further illustrate the predictive
capabilities of the coupled contact pressure and wear model, a
two-component polymer sample was fabricated and experimentally
evaluated through laboratory wear experiments. Data obtained from the
abrasive wear testing of a laboratory multicomponent polymer sample
was compared to model predictions using measured system and material
parameters. Differences between the measured and predicted surface
profiles were on the same order as the sample’s surface roughness (Ra
~3 µm).