Aalenian–Lower Bajocian Foraminiferal Fauna from the Ammonitico Rosso Series of Bakonycsernye (Hungary). Part 1: Taxonomy and Biostratigraphy

This paper provides the first record of isolated foraminiferal assemblages from the continuous Aalenian–lower Bajocian succession from the pelagic region of the Neotethys. The studied Tűzkövesárok section B of Bakonycsernye (Hungary) has been well dated by ammonites and consists of Ammonitico Rosso type limestones. The foraminiferal fauna extracted by glacial acetic acid yielded 49 benthic taxa (species and subspecies); protoglobigerinids also occurred. Most specimens belonged to the suborder Spirillinina, followed by the suborder Lagenina and Rotaliina; agglutinated forms were subordinate and miliolids were absent. The majority of the species have wide stratigraphic ranges; moreover, the distributions of 11 species changed based on their appearances in this section. Nevertheless, the Aalenian and Bajocian parts of the section could be distinguished based upon the stratigraphic distributions of some species.