Els cricètids del miocè inferior de la conca del vallès-penedès (catalunya): taxonomia, bioestratigrafia i implicacions paleoecològiques
- Autores: Silvia Jovells Vaque
- Directores de la Tesis: Isaac Casanovas Vilar (dir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2020
- Idioma: español
- ISBN: 9788449095993
- Tribunal Calificador de la Tesis: J. Flynn Lawrence (presid.), Judit Marigó Cortés (secret.), Pablo Peláez-Campomanes de Labra (voc.)
- Programa de doctorado: Programa de Doctorado en Biodiversidad por la Universidad Autónoma de Barcelona y la Universidad de Barcelona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
The early and early middle Miocene (late Ramblian to middle Aragonian; ca. 19-15 Ma) rodent record of the Vallès-Penedès Basin (Catalonia, north-eastern Spain) is far richer and more continuous than previously thought. This thesis is centered in the description of the cricetid fauna from this time interval and its biostratigrahical, paleobiogeographical and paleoenvironmental implications.
The systematic study of the cricetid fauna of all known early and early middle Mio¬cene sites from the Vallès-Penedès Basin defines the main body of this work. The studied material comprises nearly 1,000 isolated molars as well as some mandibular fragments and even a partial skull. Four cricetid genera occur in the early to early middle Miocene (late Ramblian-middle Aragonian, MN3-MN5) record of the Vallès-Penedès Basin. The archaic cricetid Melissiodon dominans is common during Ramblian zone A (ca. 19.3-17.2 Ma) a before the dispersal of the so-called ‘modern cricetids’ of the genera Democricetodon and Megacricetodon. Modern cricetids are dominant components ofAragonian zone C and early zone D faunas (ca. 16.5-15 Ma) and include four species of the genus Democricetodon (D. hispanicus, D. cf. decipiens, D. gracilis, D. sp. 4) and one of the genus Megacricetodon (M. primitivus). The paracricetodontine Eumyarion weinfurteri and the last Melissiodon dom¬inans complete the cricetid assemblage, but both species are generally rare. Overall the early Miocene cricetid succession shows several affinities with that from the Aragonian type area, the Calatayud-Montalbán Basin (Aragon, east-central Spain) allowing the use of the same high-resolution local biostratigraphy, with only minor differences. Moreover, Vallès-Penedès faunas also show a few similarities with the central European ones. Biostra¬tigraphical results are combined with novel magnetostratigraphic data allow constraining the age of several major regional to continental bioevents that characterize the early Mio¬cene, including dispersal events from other continents into Western Europe.
Finally, small mammal faunas are used to reconstruct regional paleoclimate be¬tween ca. 19 and 15 Ma and to compare it with other Western Europe records. Rainfall patterns are inferred from small-mammal community structure and indicate regional arid¬ification coinciding with the height of the mid-Miocene Climatic Optimum between 16.5 and 15 Ma. The Vallès-Penedès is further recognized as a transitional area between the forested and humid central European bioprovince and the more arid and rainfall seasonal inner Iberian bioprovince. Such situation, which had previously been recognized for the middle and early late Miocene already existed at the beginning of this epoch.
