Research paper

ParonicerasFrechiella, 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.
Corresponding author


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

(Spanish only)