Las primeras huellas de vertebrados triásicos de Albacete en las XXXIX Jornadas de la SEP

Durante las recientes XXXIX Jornadas de la Sociedad Española de Paleontología celebradas en A Coruña se presentó en formato póster una comunicación sobre el descubrimiento de las primeras huellas fósiles de vertebrados del Triásico en la provincia de Albacete. Halladas en el término municipal de Bogarra, se trata de un yacimiento con tres huellas, dos de pies y una de mano, que forman parte de un rastro, sobre depósitos de lutitas y arenisca dentro de las Facies Buntsandstein. Estas son pentadáctilas, con las marcas de los dedos colapsadas por el barro, con una diferencia del tamaño entre el pie y la mano bastante notable. La morfología de las huellas permite asignarlas tentativamente al grupo de icnogéneros Chirotherium/Isochirotherium/Brachychirotherium, concretamente a Isochirotherium, los cuales se asocian con arcosaurios crurotarsales. La superficie donde se encuentran estas marcas está formada por lutitas con marmorización por actividad edáfica, que, al ser un tipo de roca tan frágil, se encuentra muy diaclasada y erosionada, lo que pone en peligro la estabilidad del yacimiento. Por ello, en futuros estudios se evaluará la forma de conservar y proteger un yacimiento único en la zona. A continuación, el resumen de dicha presentación:

Although they have not received much attention in the past, the ichnological record of Triassic vertebrates from the Iberian Peninsula has increased significantly in recent years, with particularly relevant contexts from the Middle Triassic in northeastern Spain. Here it is presented a set of three ichnites interpreted as part of a trail recently found in the municipality of Bogarra (Albacete). The site was discovered on top of a reddish silt layer with evidence of edaphic activity, deposited in a fluvial plain during the Middle-Lower Triassic (Buntsandstein facies). This interpreted trackway consists of two footprints (left and right) and a handprint (left). Both the left footprint and the handprint are in association and best preserved. The footprints are pentadactyl and digitating, of some depth and with mud collapse in the digits. They are longer than wide in the feet and wider than long in the hand, with a length/width ratio of 1.277 and 0.659 respectively. As for the morphology of the digits of the foot, digit I is thin, short and parallel to digit II. Digits II and III are of equal length and both are the longest digits in the footprint. Digit IV is robust and longer than digit I. Digit V is characterized by the impression of the metatarsal pad.

The overall morphology of the footprint and its features are consistent with the group of Chirotherium-Isochirotherium-Brachychirotherium ichnogenera, tentatively assigning this track to the ichnogenus Isochirotherium. Accordingly, the organism believed to have produced the trace was probably a crurotarsal archosaur, with a length of 2 to 3 meters.

It is considered that, given the context in which it is located, this site has significant didactic, informative and scientific potential. In addition, it is considered that the site requires a conservation and restoration plan that will be evaluated in future efforts.

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Más información:

• Referencia: García-Vizcaíno, A., Mestres, S., Mora, J., Ortega, F. First record of vertebrate tracks in the Middle-Lower Triassic of Albacete (Spain). In Moncunill-Solé, B., Blanco, A., Grandal d’Anglade, A., González Fortes, G., Santos Fidalgo, L., Bao, R. (Eds.), Libro de resúmenes de las XXXIX Jornadas SEP. Paleontological Publications 5, 179.