Tillett was a bit speculative with all of his hybrid annotations and provided several names that could be associated with this hybrid. It seems rather arbitrary to choose this name, which has never been applied in the literature outside of that 1967 paper, despite several papers on hybrids and it would be far more informative to leave as a hybrid, in my opinion, as anyone seeking to make sense of this name will need to find that (rather obscure) paper to figure out what it is.

@ericlopresti : please send a feedback to POWO if you have any literature to share : https://powo.science.kew.org/contact

he names five taxa that are maritima x umbellata in that paper - alba, insularis, neurophylla, platyphylla, and variabilis - why did POWO choose alba? probably just because it was first described and first listed, but he does not formally make one taxa there, just noting that those five represent this hybrid combination.

ok, that's fine if that's code and iNat is invariant on that. for the purposes of usability and since nobody has used that name in over 50 years (despite study of that hybrid) and I may be the only person alive that's read that paper, i'm going to retract all my IDs to the genus level, just to avoid the confusion.

i don't actually doubt you are correct and this is how it is technically supposed to go, but i think it reduces usability. species and genera change names constantly, and they should be updated, hybrids seem a bit murkier, since iNat has a great way to deal with them already, which is understood by all.

i will note that for some reason you skipped the more common hybrid that also was named in that same paper (x. minor), though the type material of that from Standley actually refers to a totally different hybrid combination (Tillett calls it latifolia x umbellata, but the type is pogonantha x umbellata), making the arbitrariness of this rather more glaring, though my reading of the code you cite there makes it seem like that is actually the correct name for latifolia x umbellata now, since it was published as such, even though it is incorrect?

i've spent 1000's of hours annotating Abronia records on iNat and in many herbaria and it just seems rather backwards to me to do it this way, rather than a way that is understandable without reading long-forgotten papers with (hybrid, not real species) names that are not in common parlance, and are just going to be meaningless to 95% of the users. i just retracted my IDs, but didn't disagree with it, so you are fine.

Yes, I know that the species was described then. Alice Eastwood named A. alba in 1897 for a hybrid of umbellata and maritima; in his generic revision, Paul Standley added 4 more species names (insularis, neurophylla, platyphylla, variabilis) in 1909 to various instances of this hybrid. To the best of my knowledge, the only specimen every recorded for alba was Eastwood's type.

In 1967, Tillett noted that all those referred to hybrids of umbellata and maritima, which are very common in Southern California. Despite the hybrid being mentioned in several papers (and indeed hybridization the focus of at least two), the x. alba name was never used again. So, it was used once in 1897 and once in 1967, and despite a plenty of physical specimens (I have collected it) and study, the name didn't stick.

More germane to this is that iNat doesn't actually say you need to follow the code for hybrids. They say, in their curator guide:

"Given their vague morphological delineation and taxonomic uncertainty, use of hybrid taxon concepts should be avoided whenever possible. Adding IDs of higher-level taxa is usually sufficient. In those rare cases when some external authority actually supports a named hybrid, we will tolerate it, but abide by the following guidelines.

Hybrids between species should have scientific names (the name associated with the taxon) following the pattern GENUS SPECIES1 × SPECIES2, e.g. Dryobates nuttallii × scalaris for a hybrid between Dryobates nuttallii and Dryobates scalaris. The rank for such hybrids should be set to "hybrid." Note that the cross character is "×" and not the Roman letter "x.""

I read that as we can absolutely still use - and probably should - use the umbellata x maritima name here? Is there further/more detailed guidance available?

@ericlopresti : this is for unnamed hybrids.
INat says that POWO is the reference for vascular plants on iNaturalist, and POWO has a name for this hybrid, following the Code.

It is a little bit disturbing that you have spent many hours annotating specimens in herbaria without any knowledge of the Code.

"a little disturbing" and "without any knowledge of"? get off your high horse - i don't know the intricacies of hybrids, for sure, but I'm one of few people who have studied this group. i'm trying to help here on a public platform with a group that I know well, to help with a genus without many good ID resources. i'll defer to everyone else's expertise here. i'll not belabor this point farther.

Actually, I missed it since they are not in the lists of species or in the keys, though all of those hybrid names are mention in a note in the Jepson treatment of the genus by @andymurdock , noting that they "do not deserve taxonomic recognition".

Hmm... this change does seem a little unhelpful. Any taxonomy requires some subjective decisions. iNat tries to minimize that by defaulting to external authorities such as POWO. But there are valid reasons to diverge from these authorities when necessary. iNat takes a fairly conservative view on hybrids (e.g. only add natural hybrids and then not often). These Abronia hybrids do meet those criteria, in my view, because they do occur regularly and there is scientific value to recording them.

If there is a well-established nothotaxon then that's the name to use, but otherwise, it's clear how to construct a hybrid species formula such as the one that was used here.

In this case, as @ericlopresti points out, the nothotaxon Abronia × alba listed by POWO is (1) essentially unused, (2) one of five used for the same parentage, (3) deprecated by the Jepson treatment, which is typically regarded as authoritative for California plants. I would also add that the name is (4) confusing, as few of these hybrids have white flowers, in contrast with the name "alba".

I understand @t_e_d's arguments about the ICN. However, the proposal here is not to favor a later nothotaxon name over an earlier one, but to favor the hybrid formula name (which has been used extensively) over a nothotaxon that has been used twice in the past 120 years. Even well-recognized nothotaxa also can be referred to by their hybrid formula; in this case, we can make the choice not to use the nothotaxon name, because we're not compelled to. (And that's a qualitatively different choice than arbitrarily prioritizing a later name, which ICN rightly rejects.)

No disrespect to @t_e_d, but I really do think that the hybrid formula is a better choice here and should be restored (with Abronia × alba as a synonym). Perhaps @loarie can give us an opinion here?

Hi @t_e_d. Sorry, I edited my comment above to add some extra context. I get your points, but I also disagree with them.

1. POWO unearthing a very old hybrid name is not the same thing as POWO unearthing a valid name for a species or infrataxon.
2. Eric's and my point about five names having been applied to this hybrid combination is very much to highlight the arbitrary nature of resurrecting × alba. I think we all know that there are rules to determine synonymy.
3. I believe Jepson actually was authoritative earlier in iNat's history (may remember that wrong), but the advent of POWO has been a great boon. I trust though that you are familiar with the concept of diverging from a taxon framework. There are various reasons to do this, but often they amount to the taxonomic authority lacking familiarity with research in a particular region. I think that's part of the issue here, but with the added aspect that iNat doesn't have a position on using a nothotaxon vs. a hybrid formula.
4. Yes. I realize that many specific epithets are wildly inaccurate. I'm just saying that here we have the discretion to use the formula instead.

Thanks @silversea_starsong. Actually, I think the crux of the matter here is not that Abronia × alba is at all invalid (I think it's a valid nothotaxon name), but that a hybrid formula such as Abronia maritima × umbellata is always valid, even when a nothotaxon name also exists. This is not the same issue as an earlier name eclipsing a later synonym.

The ICN says nothing against referring to named nothotaxa by their formula. Here's the closest piece of advice I can find:

H.2.1. A hybrid between named taxa may be indicated by placing the multiplication sign × between the names of the taxa; the whole expression is then called a hybrid formula.

And I believe iNat is free to decide whether it's more helpful to use the nothotaxon name or the hybrid formula. In this case, the evidence in favor of using the hybrid formula seems pretty strong.

If the IAPT had intended that the hybrid formula should no longer be used for species with a valid nothotaxon, I think they would have said that. Article H4.1 does not say that. It seems clear that it says the ICN only permits one nothotaxon name per hybrid formula, which is a different thing. Let's wait for @loarie or another iNat staff member to give us a viewpoint on this.

iNat (rightfully) fudges valid names in favor of useability all the time - species complexes, pairs of species with a /, etc. It would be rather difficult for anyone to arrive at the ID of Abronia x alba, since the authoritative keys (FNA/Jepson/etc.) don't have it as an option, and even, somewhat hilariously - Tillett's own key in that paper doesn't have it. So, someone confronted with getting an ID on a plant using existing resources could not get there reasonably, and anyone trying to figure out what this x. alba thing is on iNat wouldn't be able to easily look it up (POWO would be the only place) and therefore, while it is without a doubt the valid name, it just isn't useful.

The iNat guidelines are vague "In those rare cases when some external authority actually supports a named hybrid, we will tolerate it". Does "tolerate" mean "require"? (That seems a linguistic stretch, in my opinion). Or should it be something more along the lines of "support when useful"?

Thanks for taking a look @loarie. (I think) I do appreciate @t_e_d's perspective, and we can all agree that Abronia × alba is the correct nothotaxon. But the facts that (1) hybrid formulas(ae?) are a parallel naming system and (2) iNat allows deviations from POWO appear to permit using Abronia maritima × umbellata, with Abronia × alba as an iNat synonym (in ICN terms, of course it's the valid name, not a synonym).

To my mind, the thoughts of those working with these plants would be most useful here, as we're not asking about a general taxonomic principle that we all understand, but which form of usage would be most helpful to iNat users encountering these plants. I'm guessing that's a small group, but maybe we can get some thoughts from @alysonvn @alleneli @jrebman @matt_g @grnleaf or others.

As someone who works on the taxonomy of Abronia, I'd like to weigh in on this. I strongly support using the hybrid formula Abronia maritima × umbellata, and I think it would be fine to list Abronia × alba as an iNat synonym. Abronia maritima × umbellata is so much more user friendly, and is what gets used both in common parlance and in recent literature.

While were on the subject of Abronia hybrids, is there a place where we can propose more specific hybrid taxa on iNat? For example the northern variety Abronia umbellata var. breviflora is highly self-fertilizing while the southern variety Abronia umbellata var. umbellata is highly outcrossing. While hybrids with Abronia latifolia occur with both varieties, they are much more rare (and cool to track) with the selfing var. breviflora. Could we have this as two separate hybrids, especially since var. breviflora is considered "imperiled" and is therefore obscured on iNat maps? What is the pathway for requesting this?

This is relevant to my own research, where we found that the rare Abronia villosa var. aurita has formed a hybrid population with Abronia umbellata var. umbellata, while the much more widespread and common sister variety to var. aurita, Abronia villosa var. villosa, does not have any range overlap with umbellata in the US (it definitely does in Mexico/Baja, but the rare var. aurita is endemic to CA, while the common var. villosa never reaches the ocean).

@silversea_starsong Ah, sorry. I agree that Abronia x alba is a valid name, but I also agree with @ericlopresti and @rupertclayton that it is not useful.

Hi all. First, on @silversea_starsong's point.

Just going to put this out there that the matter of whether we should use a nothotaxon name or a hybrid formula name is something that should be universally agreed upon.

I have a slightly different take here. I think we need a consistent policy on how to choose an iNat name for taxa that have a valid but little-used nothotaxon (and by definition also a valid hybrid formula). But I don't think we need to universally default to either nothotaxon or hybrid formula. Both those positions would be a disservice to iNat users, as there are taxa that are unarguably more well known by their nothotaxon names and others (like this case) where the reverse is true. Always preferring one would be an example of Emerson's "foolish consistency". I would prefer to see something similar to Wikipedia's policy for article titles, which favors the most commonly recognizable name. Often the best choice will be the nothotaxon, e.g Canna × generalis, but I think Abronia × alba is a poster child for preferring a hybrid formula in some cases. Where iNat users disagree, they should flag the taxon, explain their reasoning and try to engage other users in developing consensus or at least a majority preference.

Specific to this taxon swap, I believe everyone agrees that Abronia × alba is the valid nothotaxon for plants with the (equally valid) hybrid formula Abronia maritima × umbellata. @t_e_d's position appears to be that iNat should always choose a valid nothotaxon as the taxon name, in preference to the hybrid formula. So far, the other participants support having the flexibility to use the hybrid formula in this case due to the many reasons that @ericlopresti laid out. I would suggest that if we want to expand this discussion beyond this particular instance, that might work better on the iNat forum.

@alleneli: Current iNat policy on adding hybrids to the taxonomy is pretty conservative, and is restricted mostly to documented natural hybrids that occur fairly often and have published names/formulas. That likely means that you wouldn't be able to create hybrid taxa for hybrid combinations you have uncovered in your own research. If you want to track these data on iNat, I'd recommend that you use an Observation Field instead. There's one already available called "Hybrid name" for example.

« There is no requirement by the Code that the nothotaxon name must be used; the hybrid formula is perfectly acceptable » is incorrect.
https://www.iapt-taxon.org/nomen/pages/main/art_23.html#Art23.6 (d)

The following designations are not to be regarded as species names:
(d) Formulae designating hybrids

@ericlopresti I'm not sure I have much input on which is the right name (I'd need to know more about the code and a lot more about the taxonomic history), but I would encourage you to continue adding IDs even if they fall under what you consider the wrong name. The reason has less to do with whether the name is right and more to do with how names change and how those changes are applied on iNaturalist. If we all decide further down the line that A. × alba should be treated as a synonym of A. maritima × umbellata, that is easily correctable with the click of a button if you ID as A. × alba. If the preferable name is not present on iNaturalist, I'll add the "incorrect" name as the ID and then write in the comments: "Technically [insert preferable name here]." If there are different taxon concepts at play here (i.e., if some taxonomists treat A. × alba as ONLY applying to the white flowered hybrids between A. maritima and A. umbellata), you could even add an observation field.

For what it's worth, I feel like this is a pretty good time to advocate for a taxon swap delay: https://forum.inaturalist.org/t/implement-automatic-delay-for-proposed-taxon-swaps/38701. Since the problem seems like this problem hasn't reached a conclusion yet, it seems like more discussion would have been helpful before the the swap was committed. Note also the feature request that would notify users in the last reply.