Silurian conodonts of the Obejo-Valsequillo Domain (SW of the Iberian Massif)

Trabajo presentado en el 1st International Meeting of Early-stage Researchers in Palaeontology - XIV Encuentro de Jóvenes Investigadores en Paleontología: New perspectives on the Evolution of Phanerozoic Biotas and Ecosystems, celebrado en Alpuente, Valencia (España), del 13 al 16 de abril de 2016The Obejo-Valsequillo Domain is located in the boundary area between the traditional Central-Iberian and the Ossa-Morena zones, being now regarded as part of a large allochthonous nappe emplaced onto the hinterland of the Iberian Massif. This controversy makes important the micropalaeontological studies of the small and isolated carbonated outcrops (Sarmiento and Gutiérrez-Marco, 1999) that occur in a siliciclastic context to determine their age and affinities. Conodont faunas have been found in two samples among the nine investigated, each one corresponding to one locality. The first one, Tres Mojones, is a low diversity association composed exclusively by coniform elements belonging to the species Dapsilodus obliquicostatus (Branson and Mehl) and Pseudooneotodus bicornis contiguus Corradini. The second one, Puerto Calatraveño, is composed by ramiform and pectiniform elements of Oulodus elegans detorta (Walliser), Oulodus siluricus (Branson and Mehl), Wurmiella excavata excavata? (Branson and Mehl) and “Zieglerodina remscheindensis” (Ziegler). All the specimens have been affected by taphonomic processes such as disarticulation, dissolution, clay crusting and fragmentation. In addition, the Puerto Calatraveño conodont elements exhibited three families of fissures, probably related with the proximity of the Paraneda-Valsequillo fold hinge. A Pridoli age, Lower Detortus conodont Zone, is attributed for the Puerto Calatraveño sample, based in the appearance of the index taxa Oulodus elegans detorta. For the Tres Mojones sample, a slightly older Pridoli age, with high possibilities of being Lower Detortus Zone, has been recognized by the predominance of Pseudooneotodus bicornis contiguous (Corradini, 2007). Although both samples could be attributed to the same conodont zone, the low diversity of the Tres Mojones assemblage is related with deep and low-energy offshore environment (Aldridge and Jeppson, 1984), meanwhile the Puerto Calatraveño conodonts, with higher taxonomic diversity, correspond to a near-shore environment and, probably, an open marine platformThis work has been supported by the IBEROR project (ref. CGL.2012-39471/BTE) of the Spanish Ministry of Economy and Competitiveness.Peer reviewe