IUCN Red List data observations

Observations about the data in IUCN Red List version 2026-1, gathered while preparing Red List data for Wikipedia and Wikidata and shared for the next release's data review. Each observation links to a description with a short preview, a full sortable list, and a CSV download.

Release reviewed: IUCN Red List version 2026-1
Generated: 2026-09-06
Catalogue of Life reference: COL26.7 XR (2026-07-17), used as a taxonomic comparison in the Catalogue of Life reports

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The observations most worth acting on before the next release.

Assessments with no geographic scope (52 rows) Fix by hand
These assessments drop out of scoped search, including the usual Global filter. Every row needs a look.
Stray whitespace in taxonomy fields (1,099 rows) Fix by script
Simple automated fix is possible.
Historical assessments missing from the API (3 rows) Fix by hand
The API returns 404 for each of these. Few rows, each unambiguous.
Scientific names that do not match their genus and species fields (4 rows) Fix by hand
Few rows, each a plain typo in one field.
Provisional (sp. nov.) names with a described name in another source (4 rows) Fix by hand
Few rows, each a specific described name to confirm against its publication.

Missing and outdated records

Assessments and taxa missing something: a geographic scope, an API response, an assessed parent species, a current assessment, or a described name.

Observation	Action	Rows	Since 2025-2	Open
Assessments with no geographic scope Assessments whose geographic scope is blank, so any scope filter, including the usual "Global" filter, silently drops them.	Fix by hand	52	up from 23	details · full list · csv
Historical assessments missing from the API Historical assessment ids that appear in a taxon's API record but return HTTP 404 (not found) when requested directly.	Fix by hand	3		details · full list · csv
Subspecies and varieties with no assessed parent species Assessed subspecies and varieties whose parent species has no assessment of its own, leaving them reachable only by their SIS id.	Decide policy	358	down from 383	details · full list · csv
Taxa with no current assessment Taxa whose assessments are all historical: none is flagged as current, usually because the taxon was removed, merged, or reclassified. Split by when the last assessment was published and by its scope.	Decide policy	4,218	up from 3,898	details · full list · csv
Provisional (sp. nov.) names with a described name in another source Taxa assessed under a provisional name (Genus sp. nov. 'epithet') for which the Catalogue of Life, Wikidata, or English Wikipedia now records a described name that IUCN's own synonym list does not.	Fix by hand	4		details · full list · csv

Text cleanup

Stray whitespace, markup, and values that disagree with each other in name, synonym, and narrative fields.

Observation	Action	Rows	Since 2025-2	Open
Stray whitespace in taxonomy fields Taxonomy field values with stray whitespace (leading, trailing, doubled, or non-breaking), each with a suggested cleaned-up value.	Fix by script	1,099	up from 1,095	details · full list · csv
Synonym names with whitespace irregularities Synonym names with stray whitespace (leading, trailing, doubled, or non-breaking), each with a whitespace-normalised suggestion.	Fix by script	11,827	up from 11,578	details · full list · csv
Synonym names with markup or unusual characters Synonym names containing HTML markup, stray HTML entities, or typographic quotes, each with a cleaned plain-text suggestion.	Fix by script	2,802		details · full list · csv
Notes written inside synonym names Synonyms whose name field contains a bracketed nomenclatural note, such as [orth. error], alongside the name itself.	Decide policy	2,309		details · full list · csv
English common name issues English common names with a likely error or a formatting choice worth checking (species codes, all-capitals text, stray whitespace, backticks standing in for apostrophes), with a tidied suggestion where one is clear.	Fix by hand	615		details · full list · csv
HTML and plain-text narrative fields that differ Assessments whose narrative text differs between the HTML and plain-text CSV exports, often because heavy redundant markup left the plain-text version empty or truncated.	Fix by hand	525		details · full list · csv
Scientific names that do not match their genus and species fields Assessments whose recorded scientific name does not agree with the separate genus, species, and infrarank fields it should be built from.	Fix by hand	4	unchanged	details · full list · csv
Stray whitespace and unusual characters, by taxonomy field A field-by-field profile of text irregularities in the taxonomy data, showing which fields have the most stray whitespace or unusual characters.	No action	8		details · full list · csv

Catalogue of Life crosscheck

Every assessed name is checked against the Catalogue of Life. The two pages most likely to need a change are listed here.

Observation	Action	Rows	Since 2025-2	Open
Names with a close Catalogue of Life match IUCN names that appear nowhere in the Catalogue of Life, each paired with the most similar CoL spelling and a note on how the two differ.	Fix by hand	799		details · full list · csv
Parent taxon spelled differently in the Catalogue of Life Names whose parent taxon is spelled slightly differently in IUCN and the Catalogue of Life, suggesting the same placement written two ways.	Fix by hand	94		details · full list · csv

All 10 crosscheck pages (27,901 rows), for anyone reconciling the two catalogues →