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Extinct reptile volume for Zulma Gasparini: dinosaurs, ichthyosaurs, plesiosaurs, crocodiles, turtles , squamates (in open access)



Ben Creisler
bcreisler@gmail.com

A recent publication in open access not yet mentioned.

http://www.peapaleontologica.org.ar/index.php/peapa/issue/view/19/showToc

===

Publicación Electrónica de la Asociación Paleontológica Argentina Vol
15, No 1 (2015)

Reptiles Extintos - Volumen en homenaje a Zulma Gasparini [Extinct
Reptiles--Volume in honor of Zulma Gasparini]

===

Marta Fernandez & Yanina Herrera (2015)

Reptiles extintos - Volumen en homenaje a Zulma Gasparini (VOL.
COMPLETO, 203 pp.)

http://www.peapaleontologica.org.ar/index.php/peapa/article/view/94/96

====

Marcelo de la Fuente & Juliana Sterli (2015)
Estado del conocimiento de las tortugas extintas del territorio
Argentino: una perspectiva histórica.
[State of knowledge of the extinct turtles of the  Argentine
territory:  a historical perspective.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1):  1–19
doi:  http://dx.doi.org/10.5710/PEAPA.28.09.2015.95
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/95

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/95/88

The study of extinct turtles in the Argentine territory began 157
years ago when the French naturalist Auguste Bravard nominated the
first species of turtle. Since then, the knowledge of the Testudinata
in the Argentine territory increased in a geometric progression from
mere nominations of species without any characterization, made by
naturalists and pioneers of the paleontological studies of the
nineteenth century, to the recent detailed anatomical studies. Three
different stages in the history of the study of turtles in Argentina
can be recognized. The initial stage, that lasted more than 100 years,
between 1858 and 1965, the studies were carried out by foreign and
Argentine naturalists as well as by pioneers of paleontology. The
second stage that lasted 27 years, between 1966 and 1993 in which
synthesis works have mainly done by vertebrate paleontologists and
Argentine paleoherpetologists, in some cases with the participation of
foreign experts. The last stage, between 1993 and 2015, is
characterized by significant contributions on the anatomy, taxonomy
and biogeography of Meso–Cenozoic Testudinata of the Argentine
territory.

***
El estudio de las tortugas extintas en el territorio argentino se
inició hace 157 años cuando el naturalista francés Auguste Bravard
nominó la primera especie de tortuga. Desde ese entonces hasta la
actualidad se incrementó el conocimiento de los Testudinata del
territorio argentino en una progresión geométrica, desde las meras
nominaciones de especies sin ningún tipo de caracterización,
realizadas por los natu- ralistas y los pioneros de los estudios
paleontológicos del siglo XIX, hasta los estudios anatómicos
detallados de la actualidad. Arbitrariamente hemos reconocido tres
etapas diferentes en el desarrollo de estos estudios. Una etapa
inicial que se extendió por más de 100 años y que abarcó entre
1858 y 1965 caracterizada por menciones esporádicas sobre nuevas
especies de tortugas fósiles realizadas por naturalistas extranjeros
y argentinos, así como por pioneros de la paleontología. Una segunda
etapa que abarcó 27 años comprendida entre los años 1966 y 1993 en
la que se realizaron mayormente trabajos de síntesis por parte de
paleontólogos de vertebrados y paleoherpetólogos argentinos
incluyendo, en al- gunos casos, la participación de especialistas
extranjeros. La última etapa, comprendida entre los años 1994 y
2015, está caracterizada por el estudio sistemático de las tortugas
extintas con aportes significativos sobre la anatomía, taxonomía y
biogeografía de los Testudinata meso– cenozoicos del territorio
argentino.

===

Marta S Fernandez & Lisandro Campos (2015)
Ophthalmosaurids (Ichthyosauria: Thunnosauria): alpha taxonomy, clades
and names.
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1):  20–30
doi:  http://dx.doi.org/10.5710/PEAPA.15.09.2015.96
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/96

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/96/83

Thunnosaurian ichthyosaurs represent the paradigm of reptilian body
designed for a pelagic life style. Most derived thunnosaurian, the
ophthalmosaurids, have been traditionally considered as members of a
declining lineage. New findings and the re-examination of histori- cal
collections radically changed our conceptions about them.
Opthalmosaurids were ecologically more diverse than previously
thought. The past few decades have seen an increase of nominal species
spurred by new findings and analyses. A still unresolved problem is
that many species are only known by their holotypes. Nevertheless,
morphological disparity is a compelling argument for considering them
as valid. All recent cladistic analyses of ichthyosaurs recover
ophthalmosaurids as a clade. Neither the addition of new information
nor the addition of new entities resulted in its collapse. On this
basis, the assignment of Linnaean rank to this clade
(Ophtalmosauridae) is reasonable as it satisfied the primary
recommended criteria for taxa naming: monophyly and stability. As the
lists of species and genus names are used as input in major data bases
for interpreting major turnover and/or extinction patterns, efforts
must be focused on clarifying as much as possible the alpha taxonomy.
Two major pending issues are the delimitation of
Ophthalmosaurus-Baptanodon, and Platypterygius. The case of
Platypterygius is complex because the type species is poorly known,
its holotype is lost, and there is no consensus among specialist about
the species that should be included in this genus. On the other hand,
we advocate for the use of the name Baptanodon natans instead of
Ophthalmosaurus natans.

======

Adriana M Albino & Santiago Brizuela (2015)
Avances en el conocimiento de los reptiles escamosos fósiles
continentales de América del Sur.
[Advances in the knowledge of the continental fossil squamate reptiles
of South America.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1): 31–39.
doi:  http://dx.doi.org/10.5710/PEAPA.10.09.2015.97
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/97

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/97/89

The squamates are a successful group of reptiles which includes more
than 9,600 extant species. Their evolution in South America, scarcely
illustrated by the incomplete and episodic fossil record, is a
consequence of the complex geological and paleoclimatic history of
this part of the world. The Mesozoic squamate record is concentrated
in Argentina and Brazil, with less presence in Bolivia. Both major
squamate clades (Iguania and Scleroglossa) are present during the
Cretaceous, where snakes were common and diverse, involving some of
the most primitive terrestrial forms. Paleogene and Neogene squamates
were mainly recorded in Argentina, Bolivia, Brazil, Colombia, Peru,
and Venezuela. Lizards were uncommon in Paleogene deposits but snakes
showed an important diversity which included at least two extant boid
snakes (Boa and Corallus) and extinct forms. The Miocene is especially
relevant because of the first recognition of some extant genera of
Iguanidae (Liolaemus, Pristidactylus), Teiidae (Tupinambis), and other
Boidae (Eunectes, probably Epicrates), although extinct genera were
also present. First occurrence of Colubridae is from the early
Miocene, whereas Scolecophidia appeared in the middle Miocene, and
Viperidae in the late Miocene. The earliest Amphisbaenia of South
America is recorded in the Pliocene, and the earliest Gekkonidae,
Anguidae and Elapidae come from the Pleistocene. Most Pleistocene and
Holocene squamate remains correspond to living genera, including some
extant species.

***
Los escamosos conforman un exitoso grupo de reptiles que incluye más
de 9.600 especies actuales. Su evolución en América del Sur,
escasamente ilustrada por un registro fósil incompleto y episódico,
es consecuencia de la compleja historia geológica y paleoclimá- tica
de esta parte del mundo. El registro del Mesozoico está concentrado
principalmente en Argentina y Brasil, con menor presencia en Boli-
via. Los principales clados de reptiles escamosos (Iguania y
Scleroglossa) aparecen en el registro durante el Cretácico, donde las
serpientes eran comunes y diversas, con algunas de las más primitivas
formas terrestres. Los escamosos del Paleógeno y Neógeno provienen
princi- palmente de Argentina, Bolivia, Brasil, Colombia, Perú y
Venezuela. Los lagartos eran poco comunes en el Paleógeno pero las
serpientes muestran una importante diversidad que incluye al menos dos
boideos actuales (Boa y Corallus) y formas extintas. El Mioceno es
especialmente relevante ya que se reconocen por primera vez algunos
géneros actuales de Iguanidae (Liolaemus, Pristidactylus), Teiidae
(Tupinambis) y otros Boidae (Eunectes, probablemente Epicrates),
aunque también existen géneros extintos. La primera ocurrencia de
Colubridae corres- ponde al Mioceno temprano, mientras que los
Scolecophidia aparecen en el registro durante el Mioceno medio y los
Viperidae en el Mioceno tardío. El más antiguo Amphisbaenia
sudamericano es registrado en el Plioceno y los primeros Gekkonidae,
Anguidae y Elapidae son del Pleis- toceno. La mayoría de los
escamosos del Pleistoceno y Holoceno corresponden a géneros actuales,
incluyendo algunas especies vivientes.


=========

María Eurídice Páramo Fonseca (2015)
Estado actual del conocimiento de los reptiles marinos Cretácicos de Colombia.
[State of knowledge of the Cretaceous marine reptiles of Colombia.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1):  40–57
doi: http://dx.doi.org/10.5710/PEAPA.12.06.2015.98
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/98

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/98/84

This article intends to show the current state of knowledge of the
Cretaceous marine reptiles of Colombia. A brief historical overview of
the conducted studies is offered, an overview of taxa is provided and
some aspects of their geographic and stratigraphic distribution are
discussed. The review carried out reveals that in the Cretaceous
marine sediments of Colombia the remains of marine reptiles are
plentiful and include fossils of turtles, plesiosaurs, ichthyosaurs
and mosasaurs. Although the literature on this material is still
scarce, the increased participation of national researchers in the
study of the remains of marine reptiles provides an encouraging
panorama for the development of this branch of paleontology in
Colombia. The studies and descriptions made offer the first bases to
suggest that there were changes in the distribution, assemblage and
abundance of the different groups that inhabited the Colombian sea
throughout the Cretaceous. Turtles, ichthyosaurs and pliosauroids show
a geographic and temporal distribution limited to the marine
ingression (Early Cretaceous), while the plesiosauroids extend its
distribution until the time of maximum flooding (Turonian). The
mosasaurs appear during the major inundation and remain in the
Colombian sea throughout the Late Cretaceous.
****

En este artículo se pretende mostrar el estado actual del
conocimiento de los reptiles marinos cretácicos de Colombia. Se
ofrece una breve síntesis histórica de los estudios realizados, se
brinda un panorama de los taxones presentes y se discuten algunos
aspectos de su distribución geográfica y estratigráfica. La
revisión realizada revela que en los sedimentos marinos cretácicos
de Colombia los restos de repti- les marinos son abundantes e incluyen
fósiles de tortugas, plesiosaurios, ictiosaurios y mosasaurios.
Aunque las publicaciones sobre este material son aún escasas, el
incremento de la participación de investigadores nacionales en el
estudio de los restos de reptiles marinos ofrece un panorama alentador
para el desarrollo de esta rama de la paleontología en Colombia. Los
estudios y descripciones realizados ofrecen las primeras bases para
sugerir que hubo cambios en la distribución, asociación y abundancia
de los distintos grupos que habitaron el mar colom- biano a lo largo
del Cretácico. Las tortugas, los ictiosaurios y los pliosauroideos
tienen una distribución limitada geográficamente y temporal- mente a
los inicios de la ingresión marina (Cretácico Temprano), mientras
los plesiosauroideos amplían su distribución hasta el tiempo de la
mayor inundación (Turoniense). Los mosasaurios aparecen con la mayor
inundación y permanecen en el mar colombiano durante todo el Cre-
tácico Tardío.

====

Nathalie Bardet & Alain Galoyer (2015)
The lost world of Georges Cuvier: mosasaurids from the Campanian
Meudon chalk (France).
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1): 58–68
doi: http://dx.doi.org/10.5710/PEAPA.20.08.2015.99
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/99

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/99/86

The Late Campanian white Chalk of Meudon, a city located in the
suburbs of Paris (France), has yielded during the 19th century several
mosasaurid remains consisting mainly in isolated teeth, most being
nowadays lost. These specimens, which history is associated to the
most famous French palaeontologists of that time like Georges Cuvier,
Paul Gervais and Albert Gaudry, represent the earliest mosasaurid
discoveries from France. As such, they are precious and unique
witnesses of a lost world. In this paper, an historical approach has
been privileged, focusing on the history of their discovery and how
they were originally perceived and interpreted by Cuvier and others.
On a systematical point of view, the material is referred mostly to
indeterminate species of the tylosaurine genus Hainosaurus but also of
the plio- platecarpine Plioplatecarpus and possibly of the mosasaurine
Prognathodon, attesting of the occurrence of the three major clades of
mosasaurids in this Late Campanian marine vertebrate fauna of France.

======

Alejandro Otero & Leonardo Salgado (2015)
El registro de Sauropodomorpha (Dinosauria) de la Argentina.
[The record of  Sauropodomorpha (Dinosauria) of Argentina.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1):  69–89.
doi: http://dx.doi.org/10.5710/PEAPA.04.06.2015.100
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/100

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/100/85

Sauropodomorpha includes the most abundant and diverse herbivorous
dinosaurs, with a worldwide record. In Argentina, its record is
particularly rich and abundant, and its taxa have shed light to the
most important milestones in the evolutionary history of this group of
saurischian dinosaurs. The origin of Sauropodomorpha, the transition
to Sauropoda and the diversification of Diplodocoidea and Macronaria
are largely exemplified by the Mesozoic record from Argentina. In this
contribution the updated record of the Sauropodomorpha genera of
Argentina, including data on the geographic and stratigraphic record,
origin and phylogenetic relationships, is presented.

***

Sauropodomorpha comprende a los dinosaurios herbívoros más
abundantes y diversos, con un registro global. En la Argentina su
registro es particularmente rico y abundante y sus taxones han dado
luz a los hitos más importantes de la historia evolutiva de este
grupo de dinosaurios saurisquios. El origen de Sauropodomorpha, la
transición hacia Sauropoda, así como la diversificación de
Diplodocoidea y Macronaria son, en gran medida, ejemplificados por el
registro proveniente de las capas mesozoicas de la Argentina. En esta
contribución se presenta el registro actualizado de los géneros
válidos de Sauropodomorpha de la Argentina, incluyendo datos sobre la
procedencia geográ- fica y estratigráfica y relaciones
filogenéticas.


=====

Xabier Pereda-Suberbiola, Ignacio Díaz-Martínez, Leonardo Salgado &
Silvina de Valais (2015)
Síntesis del registro fósil de dinosaurios tireóforos en Gondwana.
[Fossil record of thyreophoran dinosaurs in Gondwana: a synthesis.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1):  90–107.
doi: http://dx.doi.org/10.5710/PEAPA.21.07.2015.101
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/101

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/101/91


Thyreophora is a clade of ornithischian dinosaurs composed of
stegosaurs, ankylosaurs, and basal forms such as Scelidosaurus.
Thyreophorans have a long fossil record, extending from the Lower
Jurassic to the Upper Cretaceous. Most of the fossils come from
localities in the Northern Hemisphere. However, the thyreophoran
record of Gondwana includes significant skeletal remains and tracks in
South America, Africa, Madagascar, Australia, New Zealand and
Antarctica. Thyreophorans could be present in Africa since the
Early–Middle Jurassic. They are well documented in the Upper Jurassic
of Tanzania (stegosaur Kentrosaurus) and the Jurassic–Cretaceous
transition of Bolivia (tracks). Stegosaurs were present in South
Africa (Paranthodon) and Argentina (indeterminate form) during the
Early Cretaceous, whereas ankylosaurs were present at this time in
Australia (Minmi). Ankylosaurs have been recorded in the Late
Cretaceous of South America (body fossils in Argentina and tracks in
Bolivia), Antarctica (Antarctopelta), New Zealand, and likely
Madagascar. The presence of both ankylosaurs and stegosaurus in India
needs to be confirmed. From a palaeobiogeographical point of view, it
seems that Gondwanan thyreophorans come from different migrations from
Laurasia. The African stegosaurs could be the result of two
independent dispersal events during the Middle–Late Jurassic. The
Gondwanan ankylosaurs do not come either from a single radiation:
Minmi may represent a relictual Jurassic ankylosaur lineage in
Australia prior to the dichotomy Nodosauridae-Ankylosauridae, whereas
the Argentinian and Antarctic nodosaurids probably represent one or
several Late Cretaceous dispersals between North and South America.

***

Thyreophora es un clado de dinosaurios ornitisquios que reúne a
estegosaurios, anquilosaurios y formas basales como Scelidosaurus. Su
registro fósil se extiende desde el Jurásico Inferior hasta el
Cretácico Superior. Muchos de los fósiles de tireóforos
descubiertos hasta la fecha provienen de yacimientos situados en el
hemisferio norte. No obstante, el registro gondwánico comprende
relevantes restos esqueléti- cos y/o icnitas en Sudamérica, África,
Madagascar, Australia, Nueva Zelanda y la Antártida. Los tireóforos
podrían estar representados en África desde el Jurásico
Inferior–Medio. Se ha documentado su presencia en el Jurásico
Superior de Tanzania (estegosaurio Kentrosaurus) y en el lí- mite
Jurásico–Cretácico de Bolivia (huellas). Durante el Cretácico
Temprano, los estegosaurios estuvieron presentes en Sudáfrica
(Paranthodon) y la Argentina (forma indeterminada), y los
anquilosaurios en Australia (Minmi). Los anquilosaurios también
tienen registro en el Cretácico Superior de Sudamérica (restos
esqueléticos en la Argentina y huellas en Bolivia), la Antártida
(Antarctopelta), Nueva Zelanda y posiblemente Madagascar. La presencia
de anquilosaurios y estegosaurios posibles en el Cretácico Superior
de la India está sin confirmar. Desde un punto de vista
paleobiogeográfico, los tireóforos gondwánicos parecen provenir de
diferentes dispersiones desde Laurasia. Los estegosaurios afri- canos
serían el testimonio de dos eventos de dispersión ocurridos durante
el Jurásico Medio–Tardío. Los anquilosaurios gondwánicos tampoco
resultan de una radiación única: Minmi podría representar un linaje
relictual establecido en Australia durante el Jurásico antes de la
dicotomía Nodosauridae-Ankylosauridae, mientras que los nodosáuridos
de la Argentina y la Antártida serían el resultado de una o varias
dispersiones desde América del Norte durante el Cretácico Tardío.


====

Ariana Paulina Carabajal (2015)
Guía para el estudio de la neuroanatomía de dinosaurios Saurischia,
con énfasis en formas sudamericanas.
[Guide to the study of the saurischian dinosaurs neuroanatomy, with
emphasis on South American forms.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1): 108–142.
doi: http://dx.doi.org/10.5710/PEAPA.15.06.2015.102
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/102

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/102/92

The neuroanatomy of dinosaurs in general is poorly understood. The
braincase is a complex structure, and its study has been increased in
the past years, due in part to the use of CT scans. Moreover, recent
studies have indicated the phylogenetic relevance of the braincase
characters. The goal of this study is to characterize the general
braincase morphology of saurischian dinosaurs, with emphasis on South
American forms, in order to stimulate new studies that will allow
increasing the knowledge of this region of the skull among dinosaurs.

***
La neuroanatomía de los dinosaurios en general es poco conocida. El
neurocráneo es una estructura compleja cuyo estudio se ha
incrementado en los últimos años debido, en parte, al uso de
tomografías computadas. Más aún, estudios recientes han indicado la
relevancia filogenética que presentan los caracteres neurocraneanos.
El propósito del presente estudio es la caracterización de la
morfología general del neurocráneo de dinosaurios Saurischia, con
énfasis en las formas sudamericanas, con el fin de incentivar nuevos
estudios que permitan incrementar el conocimiento de este sector del
cráneo en los dinosaurios.

======

Paula Bona & Francisco Barrios (2015)
The Alligatoroidea of Argentina: an update of its fossil record.
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1): 143–158.
doi: http://dx.doi.org/10.5710/PEAPA.15.06.2015.103
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/103

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/103/93

The fossil record of Alligatoroidea in Argentina is mainly represented
by Caimaninae alligatorids. This lineage recorded two impor- tant
moments in its natural history, one at the beginning of the Paleogene
(Late Paleocene–Middle Eocene) and the other in the Neogene (Late
Miocene). The most ancient record of alligatoroids in South America
comes from the Early Paleocene of Patagonia. It includes basal forms
of caimanines such as Necrosuchus ionensis, Eocaiman palaeocenicus,
Eocaiman cavernensis, and probably a new species of alligatoroid,
which provide key morphological information on the evolutionary and
biogeographic history of these crocodylians. Another important moment
of the evolutionary history of caimanines is the diversification of
the lineage observed during the Miocene. Although there is some
isolated cranial material of caimanines from the Late Miocene of
northwestern Argentina, the most abundant and diverse fossil Miocene
material comes from the northeast, from a level informally called
“Conglomerado Osífero”. Two genera of caimanines are known from this
stratigraphic level (Caiman and Mourasuchus) with at least five valid
species. Here we present an update of the knowledge of Cenozoic
alligatorids of Argentina, as a tribute to Zulma Gasparini for her
invaluable contribution to the understanding of the crocodilian
evolution in South America.

===

Yanina Herrera (2015)
Metriorhynchidae (Crocodylomorpha: Thalattosuchia) from Upper
Jurassic–Lower Cretaceous of Neuquén Basin (Argentina), with comments
on the natural casts of the brain.
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1): 159–171.
doi: http://dx.doi.org/10.5710/PEAPA.09.06.2015.104
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/104

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/104/97

Metriorhynchidae was the only Crocodylomorpha with a pelagic marine
lifestyle. Related to this lifestyle, its peculiar body plan al- lows
clearly differentiate them from others Crocodylomorpha. The fossil
record of metriorhynchids from Tithonian–Berriasian levels of the Vaca
Muerta Formation (Neuquén Basin, Argentina) is outstanding, in terms
of quantitative and qualitative record. Its taxonomical diversity is
composed by four taxa: Cricosaurus araucanensis, Cricosaurus
lithographicus, Dakosaurus andiniensis, and Purranisaurus potens. This
fossil record is also characterized by the tridimensional preservation
of the materials and by the preservation of numerous natural endocasts
of the skull cavities. Here, I made a description of the natural
endocasts of the brain of Cricosaurus araucanensis together with a
synthesis of the advances in the knowledge of these four taxa that
were performed during the last years. The information that provides
the endocasts, to- gether with the quantity of endocasts, make of the
Patagonian fossil record of metriorhynchids a key to the exploration
and reconstruction of soft anatomy of these crocodylomorphs, and for
the understanding of the physiological changes that accompanied the
structural changes of the skeleton. Understanding these changes will
allow defining the key innovations that allowed to the metriorhynchids
conquer the pelagic environment, unparalleled among archosaurs.

=====


Diego Pol & Juan Martín Leardi (2015)
Diversity patterns of Notosuchia (Crocodyliformes, Mesoeucrocodylia)
during the Cretaceous of Gondwana.
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1): 172–186.
doi: http://dx.doi.org/10.5710/PEAPA.10.06.2015.108
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/108

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/108/82


Notosuchia is a diverse clade of Crocodyliformes that achieved a
remarkable diversity during the Cretaceous. This group is particu-
larly abundant in continental deposits of Gondwana throughout the
Cretaceous, especially in South America. Notosuchia was first
recognized as a distinct group by the early work of Gasparini in the
1970’s and in the last decades numerous discoveries and studies have
increased the geographical, temporal and taxonomical scope of this
clade. Here we analyze the patterns of diversity of Notosuchia during
the Creta- ceous, considering their taxic and phylogenetic diversity,
as well as implementing sampling corrections aiming to account for the
uneven fossil record of different stages of the Cretaceous. We
identify two subsequent pulses of diversification in the late Early
Cretaceous and the middle Late Cretaceous, followed by two separate
extinction events that occurred during the latest Cretaceous
(Campanian/Maastricht- ian). We discuss the contribution of the South
American, African, and Malagasy fossil records to the diversity
curves, which indicates the African fossil record dominates the first
pulse of diversification and the South American fossil record
exclusively compose the second pulse of diver- sification. Finally, we
analyze the patterns of diversity shown by the different subclades of
Notosuchia throughout the Cretaceous, which reveal markedly different
evolutionary dynamics of four major groups of notosuchian
crocodyliforms.


===

José O´Gorman (2015)
Plesiosaurs (Diapsida, Sauropterygia) from Late Cretaceous (Late
Campanian–Early Maastrichtian) marginal marine environments from North
Patagonia.
In: Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina
15(1): 187–195.
doi:  http://dx.doi.org/10.5710/PEAPA.13.05.2015.105
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/105/94

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/105/94

During the late Campanian and early Maastrichtian, Northern Patagonia
suffered the first stage of the Atlantic marine ingression that
reached the Neuquén Basin. The Allen and La Colonia formations show
the early stages of this change, and were deposited in a complex asso-
ciation of marginal marine environments, including coastal and marine
deposits (i.e., flood plains, estuaries and lagoons). The plesiosaurs
from the Allen and La Colonia formations included at least three
species, each with a distinctive morphotype, representing a high
diversity in the Late Cretaceous. The only species that preserved
cranial material, Sulcusuchus erraini Gasparini and Spalleti, is a
strange polycotylid characterized by the presence of deep grooves in
the rostrum and mandible. The other two species correspond to
aristonectine and non-aristonectine elasmosaurids. The former are
distinguished by relatively large skulls and a high number of teeth
compared to other elasmosaurids, whereas the non-aristonectine
elasmosaurids are characterized by their relatively small body sizes,
despite being adult specimens.


===


Marianella Talevi (2015)
Microestructura ósea y suministro sanguíneo de una vértebra caudal de
un elasmosáurido (Plesiosauria, Elasmosauridae) del Maastrichtiense
(Cretácico Tardío) de la Antártida.
[Bone  microstructure and blood supply of a caudal vertebra of an
elasmosaurid (Plesiosauria, Elasmosauridae) from the Maastrichtian
(Late Cretaceous) of Antarctica.]
In: M. Fernández y Y. Herrera (Eds.) Reptiles Extintos - Volumen en
Homenaje a Zulma Gasparini.
Publicación Electrónica de la Asociación Paleontológica Argentina 15(1): 196–203
doi : http://dx.doi.org/10.5710/PEAPA.01.06.2015.106
http://www.peapaleontologica.org.ar/index.php/peapa/article/view/106

pdf:
http://www.peapaleontologica.org.ar/index.php/peapa/article/download/106/95

Plesiosaurs were reptiles recognized as a derivative from
eosauropterygians clade, whose biochron extends from the Late Triassic
to the Late Cretaceous. Plesiosaurs are recorded in marine sediments
from all continents, including Antarctica. Within this group, the
degree of compaction and organization of bone tissue are characters
that have been used to determine ontogenetic stages from which it
differs a typical juvenile pattern (dense tissue=paquiostotic), adult
pattern (light=osteoporotic tissue). In this contribution, different
cross sections were made to caudal vertebrae from a plesiosaur
recovered from the snow Hill Island Formation (Lower Maastrichtian),
Vega Island, Antarctica, with the aim of analyzing how the degree of
compaction and remodeling varies. The results show that the external
(fusion of the neural arch to the vertebral body) and the internal
ones (extensively remodelled tissue) are consistent, and suggest that
the analyzed element has adult characteristics. The element analyzed
shows a compact internal structure and this suggest that (contrary to
what previous course) the degree of compaction of a bone would not be
a good indicator of the maturation stage of the individual at least in
plesiosaurs. There is a variation of bone tissues within the vertebral
body. The caudal vertebrae has a large nutrient foramen in the ventral
region that continues inside the vertebral body with a large channel
connected with sinus that allows us to infer a conspicuous blood
supply inside the vertebral body.

***

Los plesiosaurios son reptiles reconocidos como un clado derivado de
eosauropterigios, cuyo biocrón se extiende desde el Triásico Tardío
hasta el Cretácico Tardío. su registro fósil los ubica en
sedimentos marinos de todos los continentes incluyendo la Antártida.
En este grupo, el grado de compactación y la organización del tejido
óseo han sido utilizados para determinar estadios ontogenéticos
relati- vos según los cuales un patrón típicamente denso
(paquiostiótico) indicaría un estadio juvenil y un patrón de tejido
liviano (osteoporótico) in- dicaría un estadio adulto. En esta
contribución se analizan diferentes secciones transversales
realizadas a un cuerpo vertebral caudal perteneciente a un
plesiosaurio recuperado de la Formación snow Hill Island
(Maastrichtiense inferior), Isla Vega, Antártida, con el objetivo de
examinar como varía el grado de compactación y de remodelación. Los
resultados muestran que las características externas (fusión del
arco neural al cuerpo vertebral) e internas (tejido ampliamente
remodelado) son consistentes y sugieren que el elemento analizado
presenta características adultas. El elemento analizado muestra una
estructura interna compacta y esto indicaría que, contrariamente a lo
supuesto previamente, el grado de compactación de un hueso no sería
un buen indicador del estadio madurativo de un individuo, al menos en
plesio- saurios. El cuerpo vertebral presenta un gran foramen nutricio
en su región ventral que se continúa en el interior del cuerpo
vertebral con un gran canal conectado con senos sanguíneos, que
permiten inferir un flujo conspicuo dentro del cuerpo vertebral.