Contribution to the Knowledge of the fossil flora and fauna of the Douro Carboniferous Basin (NW of Portugal)

The study of paleofloras and paleofaunas has played an important role in understanding the evolution of plant and animal communities and their ecosystems. In this sense, the study of Carboniferous flora and fauna contributes to the understanding of global-scale continental paleogeographic and paleoclimatic changes in the late Paleozoic time. The paleobotany and paleozoology of continental Carboniferous strata in Portugal have been thoroughly documented by several authors. Among them, Carlos Teixeira (1910– 1982) greatly contributed to the understanding of the paleontology of Carboniferous strata in Portugal, and his research has provided foundation for the current state of science knowledge. The Douro Carboniferous Basin (DCB) is one of the best known continental Carboniferous intramontane basins in Portugal where a very important and diversified Late Pennsylvanian megaflora occurs. In this framework, the São Pedro da Cova and Ermesinde areas are the important fossil localities within the DCB, where exceptional paleontological, stratigraphic and structural features are preserved. In this study, new paleontological occurrences were documented in the DCB. The new fossil specimens are from new outcrops that occur in the São Pedro da Cova and Montes da Costa regions. According the biostratigraphic data obtained, the new outcrops of both localities are assigned to early Gzhelian age. The results obtained from systematic paleontology include the identification of 42 floral species documented for the first time in the DCB, and descriptions of 11 new species, and two new animal taxa. These new fossil data include the first record in the Iberian Massif of an enigmatic Lesleya dryland flora and the arachnid Aphantomartus pustulatus. Both occurrences provide significant floral and faunal affinities and paleogeographic, paleoenvironmental and paleoclimatic constraints between Laurentia and the Iberian Massif in the Late Pennsylvanian as Pangea amalgamated in the Late Pennsylvanian. Other floral elements with different stratigraphic ages, such as Lobatopteris lamuriana Heer, Callipteridium jongmansi Bertrand, Pecopteris cf. miltonii (Artis) Brongniart and aff. Rhodeopteridium subpetiolatum Potonié, are identified and represent controversial chronostratigraphic data for the DCB. The floral taxa described herein belong mainly to orders Sphenopsida, Pteridopsida and Pteridospermopsida, and these megafloral and faunal elements provide new insights into the paleobotanical VIII FCUP Contribution to the knowledge of the fossil flora and fauna of the Douro Carboniferous Basin (NW of Portugal) diversity, paleoenvironment, paleoecology and paleoclimatic conditions of the Upper Pennsylvanian floras in the Iberian Massif. In this assessment, the new fossil data indicate that most of resident floral and faunal assemblages lived and evolved in mountain riparian environments within Variscan orogen during the Late Pennsylvanian during dry climatic intervals in the Late Pennsylvanian. Key-words: Fossil flora and fauna, new outcrops, Douro Carboniferous Basin, lower Gzhelian, São Pedro da Cova, Montes da Costa, Portugal. FCUP Contribution to the knowledge of the fossil flora and fauna of the Douro Carboniferous Basin (NW of Portugal) IX