Atlas des fossiles caractéristiques du Lias portugais

Abstract

Key-words: Liassic - Ammonites - Brachiopods - Lamellibranchs Gastropods - Paleontology - Biostratigraphy - Portugal This work represents the fust fascicle of an Atlas dedicated to the most characteristic and important fossils needed for the establishment of stratigraphie and ecological correlations within the Portuguese Liassic. The species are presented by stratigraphie order. Only some gastropods and lamellibranchs (6 species in total) are referred to for the Hetangian and Lower Sinemurian. For the Upper Sinemurian (or Lotharingian) the main part of the Atlas is concerned with Ammonites though brachiopods, gastropods and lamellibranchs are also mentioned. Owing to the scarcity of past publications the most common forros are figured or refigured. Il was considered to he of interest to include in. this paper some illustrations of poor specimens of dolomitic facies of ammonites kept in the Serviços Geol6gicos de Portugal owing to their importance in the establishment of stratigraphic correlations (Asteroceras? sp., Epophioceras? sp.). The importance of the forms described are emphasised by the biostratigraphic conclusions and sorne more precise elements about the stratigraphy and correlations during the Middle and Upper Lotharingian are also presented.