Phyto-MAP, a curated database of marine phytoplankton abundance records

Phyto-MAP v2.1.1 is a curated relational database of marine phytoplankton abundance records. It integrates 6623585 abundance observations from published, archived, and institutional sources into a common data model. Abundance values are standardised to cells L^-1 and linked to available source, sampling, temporal, geographic, depth, taxonomic, and analytical-protocol metadata. The canonical representation is the SQLite database phytomap-v2.1.1.sqlite3. Relational CSV exports and a gzip-compressed, pre-joined export with one row per abundance record provide alternative access formats. Supporting files include the database schema, a variable dictionary, a source bibliography and provenance index, citation metadata, a release manifest, SHA-256 checksums, and technical-validation documentation and code. Source-reported taxon designations and associated curation attributes are retained alongside the taxonomic classifications used in this release. Source provenance is documented at source and subsource levels; the database does not provide a universal crosswalk from every curated abundance record to an original source-row identifier. Retained zeros represent source-specific non-detection of a taxon sought under the relevant protocol, not universal ecological absence. Missing records must not be interpreted automatically as zero abundance. Differences in sampling effort, analytical methods, temporal and spatial precision, and taxonomic resolution should be considered before combining observations. The release completed a full technical-validation run with no failed assertions, execution errors, or skipped checks. One warning documented missing URLs for 2 of the 842 source entries. A compact execution summary and the procedures and limitations of the checks are included in the validation package. Dataset files are distributed individually. The accompanying phytomap-v2.1.1-validation.zip preserves the validation/ directory. Follow DOWNLOAD_README.txt to reconstruct the release directory and verify its files using checksums-sha256.txt. Phyto-MAP v2.1.1 is released under CC BY 4.0 within the scope described in LICENSE. Source-specific rights statements and attribution requirements remain applicable where relevant. Please cite the dataset version used and the contributing resources relevant to your work. This work was supported by the Simons Collaboration on Computational Biogeochemical Modeling of Marine Ecosystems/CBIOMES (grant nos. 549937, Z.V.F. and 549935, A.J.I.).