Marine palynology of the Alano di Piave Bartonian–Priabonian Global Stratotype Section and Point, NE Italy

Further strengthening the multidisciplinary stratigraphic and paleo-environmental analysis of the Global Stratotype Section and Point (GSSP) Bartonian–Priabonian boundary of the Alano di Piave section (NE Italy), here, we present a data report of a highly resolved, quantitative marine palynological study emphasizing organic walled dinoflagellate cysts (dinocysts). The ensuing dataset is interpreted in an exploratory sense through empirical paleo-ecological grouping and spectral analysis. The palynological assemblages are rich, diverse, and well-preserved, dominated by cosmopolitan, open marine dinocyst taxa, indicating a persistently distal, open marine depositional setting. Overall, the assemblages are remarkably stable, with no significant biotic reorganization recorded across the GSSP level. Evident paleo-environmental change is linked to the Middle Eocene Climatic Optimum (MECO) and its aftermath, where a sapropelic interval likely reflects a pluvial phase with enhanced runoff. Spectral analysis reveals that the influx of marginal marine dinocysts is strongly paced by the 400 kyr long eccentricity cycle. This suggests that orbital-scale climate changes, likely related to monsoonal intensity and runoff, controlled sediment transport from proximal settings. This data report includes the formal description of one new genus ( Bujakidinium gen. nov.) and four new species ( Impagidinium gedlii sp. nov., Guersteinia châteauneufii sp. nov., Guersteinia ? sluijsii sp. nov., and Bujakidinium umbellum gen. et sp. nov.). In addition, we provide an extensive taxonomic list with annotations and 18 plates with illustrations of the new taxa. A total of 52 additional plates are available in the Supplement. This data report thus provides a robust palynological framework for the Bartonian–Priabonian GSSP and will be the backbone for ensuing, more detailed analyses.