This paper deals with a new species of the calamitalean fossil-genus Annularia von Sternberg, Annularia noronhai sp. nov., from the Douro Basin (lower Stephanian C/lower Gzhelian, Upper Pennsylvanian), in north-western Portugal. A. noronhai sp. nov. is distinguished mainly by its lanceolate leaves with acuminate to caudate apices, which are characterised by having a very elongate mucro. Among the known species of Annularia, Annularia spinulosa is the most similar. In this study, we also reassess the taxonomic status of A. spinulosa based on comparisons between its type specimen (holotype) and specimens from Douro Basin described to this fossil-species.
- Douro Basin
- lower Gzhelian