Calcareous Nannofossil Database 1.0: A Global Database of the Stratigraphic and Paleogeographic Distribution of Mesozoic-Cenozoic Calcareous Nannofossils

Mesozoic–Cenozoic calcareous nannofossil biozones provide a key framework for both relative and absolute geological age control. However, the stratigraphic ranges of calcareous nannofossils show significant spatial and temporal variability, and many existing biozonations have not been updated against the latest chronostratigraphic ages. In addition, complex synonym systems have created difficulties in correlating nannofossil biozones across different regions and time intervals. We present the Calcareous Nannofossil Database 1.0—an open‑source, iterative database of calcareous nannoplankton. After taxonomic synonym checking, the database compiles the first and last occurrences of all Mesozoic–Cenozoic calcareous nannofossil taxa recorded from Extending Ocean Drilling Pursuits (eODP) database and published literature, along with regional chronostratigraphic calibrations. Calcareous Nannofossil Database 1.0 contains more than 2,600 species (revised according to latest taxonomic system) with their first and last occurrences, each correlated to the chronostratigraphic timescale of the Geologic Time Scale 2020. The database comprises 32 fields covering genus, species, fossil morphology, and related geological information—including age, locality, modern latitude and longitude, paleolatitude and paleolongitude, and biozonations. Altogether, it integrates over 150,000 records derived from more than 800 publications and drilling reports, encompassing approximately 2,000 sections and drilling sites worldwide. Calcareous Nannofossil Database 1.0 supports open access and search, based on geography, chronology, and taxonomy. It facilitates a deeper understanding of the spatial distribution and temporal evolutionary patterns of calcareous nannofossils, thereby revealing their biogeographic and evolutionary processes through Earth’s history and providing a valuable reference for the revision of calcareous nannofossil biozones.