12.7.24 , 1 comentarios

El primer registro de simosáuridos de Egipto en el 10th SECAD Meeting


Miembros del Grupo de Biología Evolutiva de la UNED han presentado durante la 10ª edición de la SECAD (SECondary ADaptation of tetrapods to life in water), celebrada en esta ocasión en la ciudad de Liège (Bélgica) durante los días 25 a 28 de junio, el trabajo titulado “First occurrence of the clade Simosauridae (Sauropterygia) in Egypt” como comunicación oral. En esta comunicación se ha presentado el primer registro del grupo de sauropterigios Simosauridae en Egipto, consistiendo en varios restos vertebrales aislados. A continuación, os dejamos el resumen perteneciente a este trabajo:

Simosauridae is a group of nothosauroid sauropterygians known from the uppermost Anisian or the lowermost Ladinian (Middle Triassic) to the Carnian (Late Triassic), having been recognized in both Europe and the Middle East. The group is relatively well characterized based on European specimens, where the type species, i.e. Simosaurus gaillardoti (from the Ladinian of France and Germany), and the recently defined Paludidraco multidentatus (from the Carnian of Spain) are known. In addition, material of simosaurids of undetermined generic and specific attribution from several European Ladinian and Carnian outcrops have also been documented. Not only isolated simosaurid bones are recognized in this continent, but also partial and even relatively complete skeletons. By contrast, the group is poorly represented in the Middle East, where it is known by scarce isolated cranial and postcranial remains, from the uppermost Anisian or the lowermost Ladinian of Saudi Arabia and Israel, most of the remains coming from the latter country. The Middle Triassic deposits of Araif El-Naqa, in Egypt, have yielded several sauropterygians remains, so far attributable to the placodont taxa Psephosauriscus sinaiticus and the problematic ‘Psephosauriscus rhombifer’, as well as unpublished material referred as attributable to indeterminate nothosaurs. Here, we report the first occurrence of the clade Simosauridae in Egypt. Its systematic and paleobiogeographical implications are discussed.

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11.7.24 , , 0 comentarios

Novedades sobre el registro de tortugas ibéricas como ponencia plenaria del Turtle Evolution Symposium 2024


La ponencia de clausura del “Turtle Evolution Symposium”, recientemente celebrado en la ciudad suiza de Friburgo, fue impartida por uno de los miembros del Grupo de Biología Evolutiva de la UNED, Adán Pérez García. En esta conferencia, titulada “Fossil turtles of the Iberian Peninsula (Southwestern Europe): new finds and ongoing research”, se habló del abundante y diverso registro de tortugas fósiles ibéricas, y de sus implicaciones para el conocimiento sobre este linaje de reptiles. El objetivo no era realizar una síntesis de lo previamente publicado sino que, partiendo de esos datos, se han mostrado tanto numerosos hallazgos recientes y sus posibles implicaciones, como expuestas algunas de las principales líneas de investigación actualmente en proceso. El resumen ha sido el siguiente:

The fossil record of turtles of the Iberian Peninsula is recognized as one of the most abundant and diverse for the European continent. The relative geographical position of the Iberian Peninsula over time has been strategic for the diachronic dispersion of numerous lineages of turtles to and from different geographical areas, not only considering other European regions, but also other continents (i.e., Africa, Asia, and North America). Numerous turtle lineages have been recognized in the Iberian context, including both stem taxa and, especially, pan-pleurodiran and pan-cryptodiran representatives. This record is well represented for almost all geological series, from the Upper Jurassic to the Holocene (with the sole exception corresponding to the Paleocene). Knowledge about the extinct turtles that lived in this region has improved significantly in the last two decades, through both the review of the previously documented specimens and the discovery and study of numerous new finds. The main objectives of this keynote talk are to show some of the latest finds carried out as a result of recent prospecting and excavation campaigns, as well as others previously performed but that remained unpublished until now; and to present some of the main research on the fossil record of Iberian turtles currently underway. Thus, not only aspects linked to the systematics of these taxa will be shown, but also new data related to other research disciplines, such as, among others, those linked to the paleobiogeography, temporal distributions, variability, or neuroanatomy.

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10.7.24 , , , , 0 comentarios

Análisis de las patologías en los caparazones de tortugas fósiles españolas en el Turtle Evolution Symposium 2024


Otra de las contribuciones presentadas por los miembros del Grupo de Biología Evolutiva de la UNED en la octava edición del Turtle Evolution Symposium (Friburgo, Suiza) fue la presentación titulada “Pathological anomalies in Cretaceous and Paleogene pleurodiran turtles of Spain: an update”. En este trabajo se presenta un análisis de las anomalías de origen patológico en los caparazones de diversos grupos de tortugas fósiles de España, evaluando las posibles etiologías y mejorando nuestra comprensión sobre su patogénesis. El estudio proporciona una perspectiva integral sobre los factores externos que influían en estas tortugas y refuta diagnósticos anteriores, ofreciendo nuevas interpretaciones sobre su paleoecología. A continuación, el resumen de dicha presentación:

Fossilized turtle shells often display anomalies of pathological origin. This provides tangible evidence that, like their current representatives, extinct turtles were also exposed to various external agents capable of compromising the shell integrity. Accurate interpretation of the shell pathologies is crucial for several purposes. Specifically, it allows to understand the paleoecology of extinct turtle species, providing insights into the diseases that have affected this lineage over time, as well as the subsequent healing stages experienced throughout the lives of these extinct organisms. In this context, our study synthesizes the main cases of pathological anomalies in the fossilized remains of different exclusively freshwater to inhabitants of brackish to marine coastal waters turtle taxa from the Spanish Upper Cretaceous and Eocene records, all of them belonging to Pan-Pleurodira (i.e., several representatives of Dortokidae, Bothremydidae, and Podocnemididae). Through this analysis, we identify diverse typologies of anomalies of pathological origin evaluating their corresponding etiologies, contributing to a deeper understanding of the various causative agents associated with prevalent shell anomalies. Likewise, we discuss previously proposed hypothetical clinical diagnoses by other authors for some specimens, refuting them by justifying different causal agents. As a result, the integration of data on anomalies of pathological origin affecting multiple taxa provides a comprehensive perspective on the diverse external factors influencing the shells of pan-pleurodiran turtles in the Spanish record, offering a better understanding of their lifestyle.

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9.7.24 , , , 0 comentarios

Reconstrucción tridimensional del cráneo de un nuevo ejemplar de Taphrosphys y estudio preliminar de su neuroanatomía en el Turtle Evolution Symposium 2024


Durante el Turtle Evolution Symposium 2024, celebrado en la localidad suiza de Friburgo, se presentó la reconstrucción tridimensional del cráneo de un nuevo ejemplar de tortuga localizada en Marruecos, e identificada como perteneciente a la especie Taphrosphys ippolitoi (Bothremydidae, Taphrosphyini). A partir de las imágenes obtenidas mediante un escáner de alta resolución y los modelos tridimensionales del cráneo, se analizaron de manera preliminar los elementos neuroanatómicos en este género de tortugas. El resumen de la comunicación es el siguiente:

Taphrosphyini was a successful lineage within Bothremydidae that inhabited several Laurasian and Gondwanan areas, from the Late Cretaceous to the Eocene. Taphrosphys is identified as the most diverse genus within Taphrosphyini, being represented by three Paleocene species, corresponding to a North American and two African forms. The cranial anatomy of all of them is relatively well-known. Although some neuroanatomical elements of several representatives of Taphrosphyini were described and figured (not for Taphrosphys, but some aspects of the endosseous labyrinth of Taphrosphys ippolitoi were considered in comparative framework), the detailed study of the neuroanatomy of no member of this clade was carried out. This contribution presents the first complete neuroanatomical study of a representative of Taphrosphyini. This is based on the analysis of an unpublished almost complete skull of Taphrosphys from Morocco, a priori attributable to Taphrosphys ippolitoi based on knowledge about the paleobiogeographic distribution of the members of this genus. It was scanned through a high-resolution micro-CT. The obtained archives were processed, generating the three-dimensional models of both the skull and the inner cavities related with neuroanatomical structures. The study of cranial characters will allow us to evaluate its specific attribution. The comparison of the endocranial and labyrinthic cavities, and the circulatory and nerve canals of this specimen with those of the representatives of Taphrosphyini in which these structures are known, but also with other bothremydids, will allow us recognizing neuroanatomical features shared by all bothremydids and, potentially, exclusive for Taphrosphyini or not shared with other representatives within this lineage.

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8.7.24 , , , 0 comentarios

Descripción preliminar del esqueleto apendicular de la tortuga Neochelys salmanticensis de la Cuenca del Duero en el Turtle Evolution Symposium 2024


En el congreso Turtle Symposium Evolution recientemente celebrado en la Universidad de Friburgo (Suiza) se ha presentado una charla sobre la descripción preliminar del esqueleto apendicular de la tortuga Neochelys salmanticensis de la Cuenca del Duero (España). En el caso del género Neochelys, solo una especie, Neochelys franzeni de Messel (Alemania), presenta elementos de su esqueleto apendicular pobremente figurado. Se ha comparado el esqueleto apendicular de Neochelys salmanticensis con otras especies de su misma familia, Podocnemididae, y se han realizado comparaciones entre adultos y juveniles para determinar diferencias ontogenéticas.

The Eocene record of vertebrates from the Duero Basin (northwestern Spain) is abundant and diverse. Several clades of turtles are recognized, highlighting, for its abundance and diversity, the podocnemidids. Two species of the European genus Neochelys have been identified. The first species described was Neochelys salmanticensis, exclusive from the Bartonian (middle Eocene) of the Salamanca Province. It is the youngest known representative of this diverse genus. For more than 50 years Neochelys salmanticensis was based on scarce material, which did not allow an adequate diagnosis. Recently, hundreds of remains (including articulated and relatively complete shells) were analysed, allowing a detailed shell characterization. Although the shell is the only element recognized in all Neochelys representatives, such a large collection has never been documented for any other species. All published information on this Spanish species is restricted to its shell. Abundant and well-preserved appendicular remains of Neochelys salmanticensis have been identified, both from the type locality and at other sites, including more than one hundred bones. As with the shell remains, the collection of appendicular bones is much larger than in any other documented representative of the genus and includes elements unknown in most other species. We present a preliminary study of the morphology of the appendicular elements of this species, based on both remains of relatively complete skeletons and isolated bones from different ontogenetic stages. Since Neochelys salmanticensis is the largest representative of the genus, morphological differences from other Neochelys species with documented appendicular bones are to be expected.

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5.7.24 , , 0 comentarios

Participación del Grupo de Biología Evolutiva de la UNED en el Turtle Evolution Symposium 2024


El Turtle Evolution Symposium (TES) es un encuentro internacional que, desde 1983, reúne a expertos en la historia evolutiva de las tortugas. Aunque en los primeros casi 30 años apenas se realizaron encuentros, desde su liberación en Canadá en 2009 se estableció una mayor regularidad, celebrándose aproximadamente cada tres años. La sede del encuentro varía en cada edición, habiéndose celebrado en varios continentes.

Este evento supone una oportunidad esencial para presentar y discutir los últimos avances en el estudio de la diversidad y evolución de las tortugas, desde su origen hasta la actualidad. Con cada edición, el simposio no solo ha ampliado el conocimiento científico sobre las tortugas, sino que también ha facilitado la creación de redes de colaboración entre investigadores de diversas partes del mundo. Este intercambio de ideas y datos es crucial para el avance en este campo y para inspirar a nuevas generaciones de científicos.


Este año, del 26 al 29 de junio, se celebró la octava edición del Turtle Evolution Symposium en la ciudad de Friburgo, en Suiza. El evento contó con la asistencia presencial de más de 40 participantes, provenientes de diversos países, así como d eotros investigadores de manera telemática. Durante el simposio, se presentaron cerca de 40 ponencias, incluyendo tres conferencias magistrales. Una de estas conferencias, correspondiente a la de clausura del congreso, fue impartida por el investigador del Grupo de Biología Evolutiva de la UNED Adán Pérez-García. Al final de esta ponencia, se ha propuesto y defendido la propuesta sobre la celebración del próximo “Turtle Evolution Symposium” en España, con sede en la UNED.


Además de esta ponencia, desde el Grupo de Biología Evolutiva de la UNED se han presentado varios resultados relacionados con diversas líneas de trabajo en tortugas mesozoicas y cenozoicas. La referencia a los resúmenes de las comunicaciones y a la conferencia invitada son las siguientes:
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