Towards the ammonite zonation of the Jurassic/Cretaceous transition: new data from ammonitico rosso/biancone sections of the Transdanubian Range (Hungary)

This paper focuses on the heavily debated Mediterranean late Tithonian-early Berriasian ammonite taxonomy and stratigraphy; therefore it also has implications for the still undefined Jurassic/ Cretaceous boundary. The content of the study presented here is based mostly on a large, typical Mediterranean ammonite fauna, which was collected several decades ago, bed-by-bed from four ammonitico rosso/biancone sections of the Bakony Mountains (Hungary). Besides, a new collecting campaign provided additional ammonite material. Details of some of the stratigraphically important ammonite taxa are summarised from a critical perspective. Stratigraphic distributions of the observed ammonite species are given section by section and the taxonomical background of the fauna is described in Supplementary Materials. Previous results from recent literature of reliable ammonite data were also taken into consideration, thus putting the Hungarian data in broader context. As a result, an updated ammonite zonal scheme for the late Tithonian-early Berriasian time interval for the Mediterranean region is suggested herein.

Automated summary

This paper discusses the debated ammonite taxonomy and stratigraphy of the late Tithonian-early Berriasian period in the Mediterranean region and proposes an updated ammonite zonal scheme for this time interval.