Distribution Maps

Occurrence records and geographic distribution of Melastomataceae species worldwide, mapped from GBIF and herbarium data.

What the maps show

Each map plots the occurrence records held for a species, using the coordinates recorded on the specimen or observation. Points are plotted as recorded: we do not interpolate ranges, draw predicted distributions, or fill gaps between records.

Why a map is not a range

Occurrence maps inherit the collection bias of the underlying herbaria. Dense clusters usually mean a well-collected region or a botanist who worked there, not a species that is abundant there. Conversely, large empty areas frequently reflect a lack of collecting rather than absence. Treat these maps as evidence of where a species has been documented, and never as evidence that it is absent elsewhere.

Known limits

• Records with a coordinate uncertainty above 50 km are excluded from the derived country lists.
• Duplicate records at the same coordinates and date are collapsed before mapping.
• Coordinate precision varies by source; museum specimens from the nineteenth century are often georeferenced to a locality centre.
• Marine and centroid coordinates occasionally present in herbarium data are not filtered out of the raw point layer.

Where the data comes from

Accepted names and authorship are reconciled against Plants of the World Online (Royal Botanic Gardens, Kew) and Tropicos (Missouri Botanical Garden). Occurrence records come from GBIF. DNA sequences come from NCBI GenBank. Conservation assessments come from the IUCN Red List, and publication metadata from Crossref. Every record keeps its original identifier so it can be traced back to the dataset it came from.

Read the full data sources and curation methodology for the field-by-field breakdown, the refresh schedule and the known limits of the data.