Mapping Documentary Gaps in Plant Occurrence Data Across Brazilian Biomes

ABSTRACT Open biodiversity records support botanical research, but their spatial coverage and taxonomic representation remain uneven. This study mapped plant occurrence documentation across Brazil using GBIF records dated from 2000 to 2025 for Angiosperms, Gymnosperms, Pteridophytes, and Bryophytes. Screening retained present occurrences with coordinates and without GBIF geospatial issue flags. Screened records were assigned to an equal‐area grid comprising 3400 cells of 50 km across six official biomes. Documentation was summarized using C2, an author‐developed procedure grouping records sharing taxonomic, temporal, geographic, and source information. Angiosperms contributed over 92% of records and clusters. Undocumented cells represented 87.8% of the grid for Gymnosperms, 77.5% for Bryophytes, 47.1% for Pteridophytes, and 10.6% for Angiosperms. Pronounced gaps occurred for Gymnosperms and Bryophytes in the Amazon, Cerrado, and Pantanal. The Atlantic Forest had the highest median documentation and source‐representation values; the Amazon had the lowest. Restriction to preserved specimens retained the country‐level ordering of undocumented‐cell proportions, whereas observations changed some comparisons. Across 25–, 50–, and 100‐km grids, undocumented‐cell proportions declined with increasing cell size, while retained territory varied. These patterns describe accessible documentation rather than biological absence. The framework supports collection review, digitisation, and data mobilization, with survey decisions additionally informed by known taxonomic distributions.