[N] 2006 Implications of theropod tracks of the Berriasian of the Iberian Peninsula
Barco, J., Canudo, J., Cuenca-Bescós, G. & Ruiz-Omañaca, J. (2006) Implications of the presence of the Megalosauripus-Therangospodus (Theropoda) in the Berriasian (Early Cretraceous) of the Iberian Peninsula. JVP 26(3) Abstracts pp.39
The Megalosauripus-Therangospodus ichnoassociation (M-Ti) is characterized by the presence of these two ichnogenera. It is well documented in the Late Jurassic of North America and Asia, and has been considered a good biostratigraphic marker for this time interval. The presence of M-Ti in sediments of the Berriasian Huérteles Alloformation (Soria) suggests that the deposit could be Late Jurassic. Our studies also recognize the M-Ti in the Villar del Arzobispo Fm (Teruel) dated with foraminifers as Early-Middle Berriasian. This does not detract from its biostratigraphical value but allows us to extend its upper limit as far as the Berriasian, at least in this region of the Iberian Plate. Since the theropod ichnological record at the base of the Cretaceous grows, it is possible that M-Ti’s will be discovered in other parts of Laurasia.
However, there is another possible interpretation for this presence within a new and interesting panorama. The break-up of Pangea at the end of the Late Jurassic brought the separation of the faunas of Laurasia and Gondwana, producing biogeographic isolation among them, as was the case with the Late Jurassic-earliest Cretaceous sauropods of northeast Iberia. The theropod skeletal record currently discovered is fragmentary and fails to shed light upon this issue. Tracks, by contrast, provide more information: the presence of the “jurassic” theropods of the M-Ti at the base of the Early Cretaceous might also be explained in terms of the presence of endemic faunas that survived through to the beginnings of the Cretaceous in some parts of the archipelago formed by the lands emerged at south Europe.