How far goes the overlap between the iNaturalist taxonomic backbone for plants and POWO as of now?

There is some post that iNaturalist started to move to the POWO taxonomic backbone for plants:

How far has this transition been going?
Is there any way to find out what taxon iNaturalist is referring to when using some species name? (API wise, I mean. When it comes to match thousands of taxon names.) Can I just assume iNaturalist will use the POWO name minus the author?


As far as I know, the major transition is complete.

I would not just assume that iNat always used POWO - there are deviations allowed. Not sure about the API, hopefully others can answer.

1 Like

In > 90% of cases, yes we match POWO, but there are still a bunch of random things which have evaded curators. I’m not sure how well these are cataloged.


not sure I’d characterise the remaining ~10% as primarily cases that have “evaded curators” – deviations are dispreferred due to clerical reasons, but are often purposefully implemented due to significant problems with POWO’s approach or current state. it is true though, yes, that there isn’t a specific catalogue of iNaturalist taxa entries that don’t match POWO, partly because it would be a mixture of explicit deviations and (indeed) things not yet examined.

1 Like

If you look at the current Taxon Framework Relationship (TFR) for vascular plants:

you will see some numbers toward the bottom that will help quantify the answer to your question. As I read the numbers:

Of the 290854 vascular plant taxa currently in the iNat backbone, there are 271868 defined TFRs, of which all except 3689 match the taxa in POWO. The other 18986 taxa without defined TFRs probably are mostly (if not all) also mis-matches (deviations) from POWO.

With 3689 explicit deviations, plus another 18986 probable implied deviations, 7.8% of current iNat taxa deviate from POWO, and 92.2% match POWO.

The iNat taxonomy is not intended to be complete for any group (although some groups are). It is updated when names are needed to identify observations. So there are an unknown (to me) number of additional vascular plant taxa accepted by POWO that have not yet been added to the iNat taxonomy.


The documented deviations from POWO definitely have not evaded curators, but there are lots of species in the iNat database which have never been flagged or reviewed by curators. Every so often a taxon is found in the dabase which has never been published and apparently only exists on iNaturalist.

1 Like

Each of the numbers noted above, including the 3689 explicit deviations and 18986 unknown relationships, is linked to a listing of the taxa / TFRs they include. (How accessible these lists are via API calls I don’t know.)

The listing of unknown relationships even includes handy links to define a relationship or make a taxon change for each name in the list, for curators who want to plug away at resolving these. Taxa currently flagged for curation are indicated prominently, and in those cases curators should assess and resolve the flag(s) first.

1 Like

Looking at the explicit deviations, most seem to be new taxa which of course make it into POWO from IPNI so all of those over a year old are no longer deviating. What is needed really is a comparison of all names with the latest POWO version and removing “deviations” where they no longer deviate and probably also the other way round.
This is of the great paradox that on the one hand iNatters jump onto new names and taxonomic changes as soon as they are published while on the other hand complaining changes are implemented too quickly without proper assessment.

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.