Ipni.org is the international plant names index for gardeners worldwide
The International Plant Names Index - home page
About the Index
The data in the IPNI comes from three sources: the Index Kewensis (IK), the Gray Card Index (GCI) and the Australian Plant Names Index (APNI). Detailed information about these indices is available through the links above. This page summarises basic information about each data source and the procedures followed in merging the records so that the user can understand the origin and the limitations of the combined dataset. For more about the data limitations and the subsequent effects on search results, read our page on understanding the data.
Geographical and historical coverage
Over one million records have come from Index Kewensis. This is global in coverage and lists names from the first edition of Linnaeus's Species Plantarum to those being published now. Basic bibliographic details are included for each name and for later records the year of publication is also included. Until 1971 infraspecific names were not included – while the Gray Index and the Australian Plant Names provide some of the infraspecific names which are lacking in IK but their coverage is not so extensive, so many names below species level are missing from IPNI. The current electronic version of the Index Kewensis was produced by an optical reading process in the mid 1980s. Despite careful checking of the scanned data, many errors were introduced into the Index at this time.
Over 350,000 records have come from the Gray Index (originally the Gray Herbarium Card Index) which includes names for New World taxa published on or after January 1886. Basic bibliographic details and date are included for each name and many records include information about types. The data were converted to electronic form in the early 1990s and much time has been invested in their standardization and verification since then. Although most of the citations in the Gray Index are for names also recorded in Index Kewensis, there are many records for New World infraspecific names which are unique to the Gray Index. The duplicate records are also of considerable value since they tend to be more detailed than the equivalent IK record and also because errors in either index can be detected by comparing records for the same name. Furthermore the Gray Index includes many records of typifications subsequent to the time of validation of a name (epi-, lecto- and neo-typifications) which are not duplicated elsewhere.
- Royal Botanic Gardens - KEW
- Richmond Surrey
- United Kingdom of Great Britain and Northern Ireland TW9 3AB