Taxonomical diversity and palaeobiogeographical affinity of belemnites from the Pliensbachian - Toarcian GSSP (Lusitanian Basin, Portugal)

For the first time, high-resolution analysis of the Late Pliensbachian - Early Toarcian belemnite assemblages from the Peniche section (Lusitanian Basin) is presented. The systematic analysis allowed the recognition of eight taxa of the suborder Belemnitina, previously reported from contemporaneous NW Tethyan and Arctic sections. The presence of Bairstowius amaliae sp. nov. in the Late Pliensbachian (Emaciatum Zone) represents a novelty since hitherto the genus Bairstowius was only known from Late Sinemurian and Early Pliensbachian deposits.  Additionally, the replacement of Bairstowius amaliae by Catateuthis longiforma, during the latest Pliensbachian, suggests an evolutionary relationship between the two taxa. This relationship suggests a new scenario for the subsequent development of endemic Toarcian Boreal-Arctic faunas, characterised by the occurrence of Catateuthis. 

The comparison of the Peniche belemnite fauna with coeval faunas from the Mediterranean/Submediterranean and Eur...