Impossible to create a new subspecies if the homonym variety is already in use

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Description of problem (please provide a set of steps we can use to replicate the issue, and make as many as you need.):

Step 1: Foeniculum vulgare lacks the nominate subspecies:

Step 2: when trying to create the nominate subspecies I have received the reply that a child taxon (I think it refers to var. vulgare) is already used

There could be the necessity to create a certain subspecies when the homonym variety still exist in iNat taxonomy. So what to do?

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I’d probably just change the var. taxon to subsp. unless there’s some reason not to.

I have to admit that the botanists’ use of subspecies and varieties – including using both in the same species and with the same name – really confuses me. Is a variety synonymous with a subspecies? Or does variety rank below subspecies taxonomically?

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There’s a schism in convention – outside the US it is more common to treat variety as a rank below subspecies. In the US they are interchangeable in current usage.

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Ok, but what if subsp. vulgaris is not already available nor I am able to create it?

The latest concept of subspecies we are using requires the existence of the geographical and/or ecological vicariances.
For variety we mean something intraspecific morphologically distinguished from the type without any geographical and/or ecological vicariance but still genetically fixed.

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I mean to edit the variety taxon in order to change the rank from variety to subspecies.

I hope I understand the problem correctly. Try to deactivate the variety, then create the subspecies. Activate the variety again and assign it to the subspecies.

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ICN Article 4.2
Variety is a rank below subspecies. They are not synonyms, nomenclaturally at least, even if that is common usage.


No need to create a new taxon, nor or inactivate the variety. As @bouteloua already mentioned,

  1. Bring up the taxon page for the variety, and put it in edit mode (only curators can do this).
  2. At the top, where Rank is set to variety, click on the drop-down list, and select subspecies for the rank.
  3. Go down to the bottom, and Save edits. The taxon has now been changed to a subspecies.

As @cooperj mentioned, the ICN allows multiple infraspecific ranks. This is rarely implemented, but when it is, rank variety is subordinate to rank subspecies.

In iNaturalist, it appears that only unique trinomial combinations can exist. So one cannot simultaneously have a subspecies, variety, and/or forma using the same epithets, even though the ranks are different.

I don’t know the functional reason for this limitation, but if it’s anticipated that classifications using multiple infraspecific ranks need to be implemented in iNaturalist, then that might need to be the subject of a feature request.


I dont think the issue is a requirement of uniqueness of trinomial names, unless it is specific to trinomials. There is no unique index or requirement names be unique. Otherwise genera in different branches of the tree of life would with identical names would fail.

The issue is the 2 ranks are considered parallel or equal in the inat hierarchy. Try creating a variety with a subspecies as its parent and you get an error about rank issues, not uniqueness of names required.

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Not quite.
Quadrinomials do not exist under ICN. Article 24.1.

“The name of an infraspecific taxon is a combination of the name of a species and an infraspecific epithet. A connecting term is used to denote the rank.”

A variety cannot officially have a subspecies as a parent. The correct formulation of an infraspecific name under ICN is a trinomial only, using one or the other rank, but that does not alter the act that the ranks variety and subspecies are not equivalent.

Correct, quadrinomials (and higher) are classifications only, not nomenclatural entities.

Interesting, I hadn’t tested that before. Since they are listed in correct ICN rank hierarchy when picking a rank, I wouldn’t have thought the infraspecific ranks were being treated any differently than the higher ranks (for parent-child purposes).

So, I suppose it’s good that iNat mirrors the ICN in only allowing infraspecific taxa to be children of species taxa.

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There is a unique index on the combination of name and parent, but not on name itself.

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Subspecies, variety, form, and infrahybrid are all essentially of equivalent rank because they are all rank level 5:

Edit: given how things are currently coded, I don’t think it’s possible to both allow a subspecies and variety of the identical trinomial, and also prevent varieties from having subspecies as parents.


Good to see that list of rank_levels, it explains a lot! Not seeing Complex in that list, does it have a rank level?

Complex is rank level 11. I’m not sure why these lists aren’t the same. I suspect they’re supposed to be, but subkingdom, subterclass, and complex each only show up on one of the two.

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Quick summary. According to the ICBN:

  • Subspecies and varieties are not synonymous, regardless of any author’s (or even a region’s) interpretation of the terms.
  • Ranks are not necessarily subordinate though they can be explicitly described as such in a taxonomic treatment.
  • This means that subspecies, varieties and forms can all be direct descendents of the species, or of another infraspecific rank.
  • The valid name is the correct combination of genus and species plus the lowest ranked name you’re using.

My opinion: This is a bug. Wherever we have valid subspecies, varieties and/or forms in the taxonomy, the autonyms should be able to be created at each rank that exists.


I guess I’m wondering, why would we ever want to have, for example, Yucca brevifolia subsp. brevifolia and Yucca brevifolia var. brevifolia both as active taxa at the same time in iNat? The only reason to do so would be if a quadrinomial classification was being used, and we’ve already established that iNat doesn’t support that. Are you saying that it should?

If so, I think that would be more along the lines of a feature request. If not, and we just have a mixture of ranks represented among the other trinomials, then the autonym only needs to exist at one rank in iNat. My suggestion would be to use the highest rank represented among the other trinomials. So if there is a mixture of varieties and forms, use variety for the autonym. If there is one or more subspecies in the mix, use subspecies.

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I see your point.

In that case, the reverse question can be asked as well: why would we have autonyms in the classification, when taxonomically they are the same as the parent species (in that they share a type). And if we do have an autonym, which rank should we assign to it, when there are infraspecies accepted at more than one rank?

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