Paroniceras, Frechiella, and Oxyparoniceras (Ammonitida) related with palaeoclimate fluctuations and regressive-transgressive cycles in the Toarcian of Spain
Departamento de Paleontología, Facultad de Ciencias Geológicas. Universidad Complutense de Madrid. Calle José Antonio Nováis, 12, 28040 Madrid, Spain. email@example.com
The record of species of Frechiella Prinz 1904, Paroniceras Bonarelli 1893, and Oxyparoniceras Guex 1974, throughout the Toarcian in the east and north of Spain, has been linked with the palaeogeographic evolution and the depositional cycles recognized in the Iberian Chain. However, the relationship between this record and the relative warming intervals and thermal peaks, pointed out by several authors in the Toarcian of Northern and East-Central part of the Iberian Subplate, is more evident. Frechiella has been recorded in the Bifrons Zone, Paroniceras in the Variabilis Zone, and Oxyparoniceras in the upper part of the Thouarsense Zone and the lower part of the Dispansum Zone. The relationships between the record of these genera and the palaeotemperatures may indicate that their species developed in warm environments. Thus, their presence in the Iberian and Cantabrian chains could be due to a migration from other areas, but not to an effective colonization.
Key words: Hildoceratidae, palaeogeography, palaeoclimatology, Jurassic, E and N Spain.
How to cite: Martínez, G. 2017. Paroniceras, Frechiella y Oxyparoniceras (Ammonitida) en relación con las ﬂuctuaciones térmicas y los ciclos transgresivo-regresivos detectados en el Toarciense de España. [Paroniceras, Frechiella, and Oxyparoniceras (Ammonitida) related with palaeoclimate ﬂ uctuations and regressive-transgressive cycles in the Toarcian of Spain]. Spanish Journal of Palaeontology, 32 (1), 109-114.
Received 30 November 2016, Accepted 27 March 2017, Published 30 June 2017