Taxonomic Swap 107443 (Tehty 21-03-2022)

Lisännyt rynxs 22. maaliskuuta 2022 01:25 | Tallentanut rynxs 21. maaliskuuta 2022
korvattu seuraavalla:


My area could now have a fuzzier distinction between "good" native, and "bad" alien Aphanes. While I hadn't yet mastered the fine distinctions between the two, and their tiny inflorescences, and tinier flower parts,
going by my area's University of Washington website, I had Aphanes occidentalis as native to Washington State, and A arvensis as introduced from Eurasia, (And I don't expect they will be going to iNaturalist to update their taxonomy.)
at the risk of possibly sacrificing some of the rarer native species, to pull out those of the common, weedy, alien species, I currently pull all Aphanes out of my work areas to make room for the rarer native species of all other genera there. I also figured that rarer native Aphanes might continue to survive in other, less disturbed, places than those I am weeding, but I had been looking forward to working out the distinctions between the native, and alien Aphanes. I might then only weed out the alien species, and, if I found any, encourage the spread of the native species. Now it could be that I would only want to weed Aphanes "arvensis" out if it is just too weedy, and outcompeting the rarer natives that I am trying to give more room to.

There are already a couple of natives that have this "too weedy" status, and that I regularly pull out to make room for the rarer natives (primarily Epilobium ciliatum, and Rubus ursinus, which is also too thorny for my work areas!). I also have one species, Galium aparine, listed as "native" in both Europe, and North America, that I weed out of almost all areas, which are generally sunny edges, but there is one area, where they grow in full shade, where they don't seem weedy, and grow in relative harmony with rarer natives there. While I know that the shade might be the main reason the G. aparine there isn't too weedy, I had theorized that those growing in that shady area were, at least primarily, of native, western Washington, gene stock, and that the rest were of primarily European gene stock. I suppose Aphanes "arvensis" could now only deserve to get weeded out if they are just too weedy in the spots I am deciding whether or not to weed them out. Alternately, I might have a DNA test on them to do on each before pulling, to determine which continent's gene stock was dominant!

Lähettänyt stewartwechsler 6 kuukautta sitten (Lippu)

I don't think any Aphanes or Alchemilla are native to the continental United States. POWO sees Aphanes occidentalis as a synonym of Alchemilla arvensis. The only resource I can find that actually recognizes Aphanes occidentalis is Jepson, which I don't trust (they have a long history of being wildly out-of-date and erratic, as well as being California-centric). I think what is seen as Aphanes occidentalis is probably just a local variant of the invasive Alchemilla arvensis, which is most definitely introduced.

Lähettänyt rynxs 6 kuukautta sitten (Lippu)

While I have the impression that iNaturalist, and its curators, tend to follow the taxonomy of Kew's Plants of the World Online - POWO in London, I don't particularly trust their taxonomy as the final word. It seems to me that local taxonomists, around the world, specializing in the taxonomy of their local species, including those that make the taxonomic decisions for the University of Washington, here in my Washington State, US, are more likely to understand the taxonomy of the plants that occur in their areas, and whether or not they are native to their local areas, better than Kew's group of POWO taxonomists in London. Multiple times I have doubted the validity of a taxonomic decision of POWO, with reason to believe that the taxonomy of my local University of Washington was more valid.

You say the only resource you that you can find that recognizes A. occidentalis is Jepson. The first three I went to, not including Jepson, recognize A. occidentalis:

University of Washington's Burke Museum, whose Aphanes page I linked to above, but I'll link to again here, recognizes A. occidentalis:

Then the second I usually go to, Flora of Oregon, also recognizes Aphanes occidentalis:

and the third I usually go to is University of British Columbia's eFlora BC, which recognizes A. occidentalis:
(enter "Aphanes")

(I tried to link to the eFlora BC Aphanes page but this comment page didn't seem to accept the long link.)

Those are the first 3 resources I went to, and the first three I usually go to for my local taxonomy, all of which recognzied A. occidentalis.


Lähettänyt stewartwechsler 6 kuukautta sitten (Lippu)

You aren't meant to "trust" POWO, just use them as a baseline.

The issue with Aphanes occidentalis is that the synonymy is disputed with European Alchemilla arvensis, which means that the issue is no longer local. Many local sources take and give to each other, propagating ideas unto one another. A good example would be the resources you've cited still using Aphanes as a distinct genus. There are many instances of previously "native species" becoming recognized as foreign following genetic studies. The only surefire method of verifying the isolation of Alchemilla occidentalis would be a genetic survey.

If you would like for a deviation, you are more than welcome to flag Alchemilla and propose the isolation of Alchemilla occidentalis. Should a number of users agree that the A. occidentalis should be distinct, then A. arvensis can be split.

Lähettänyt rynxs 6 kuukautta sitten (Lippu)

Thank you. I will consider flagging it

Lähettänyt stewartwechsler 6 kuukautta sitten (Lippu)

see for morphological differences between the 2 species. I agree with keeping the two as separate species, following all of the west coast floras.

Lähettänyt aaronliston 6 kuukautta sitten (Lippu)

@aaronliston You may also want to add your comments to the flag that you linked to.

Lähettänyt stewartwechsler 6 kuukautta sitten (Lippu)

@aaronliston it's just Jepson. The other west coast floras have followed Jepson. I believe it's the 1994 Kartesz checklist that POWO is following.

Lähettänyt rynxs 6 kuukautta sitten (Lippu)

I know that @peterzika gave this a thorough specimen and field-based assessment for the Flora of the Pacific Northwest, 2nd edition.

Lähettänyt aaronliston 6 kuukautta sitten (Lippu)

Kartesz 1994 was comprehensive, but he certainly did not evaluate the morphology of these in the field and herbarium.

Lähettänyt aaronliston 6 kuukautta sitten (Lippu)

Plants of relatively undisturbed headlands, balds, and prairies in the Pacific Northwest, called Aphanes occidentalis, have blue-green foliage and exserted flowers, and don't look like the plants native to Europe called Aphanes australis, with medium green foliage and flowers hidden within the stipules. There is some confusion, naturally, because the differences were only recently elucidated (see Flora of North America, Flora of the Pacific Northwest). In our area, in weedy settings (campgrounds, gravel roadsides, trampled trails, etc) we have introduced Aphanes australis present west of the Cascade Range in BC/OR/WA. Those plants always look larger and "greener" in the field, compared to nearby populations of A. occidentalis (smaller and grayer) in undisturbed settings. There are additional differences, measurable with a micrometer under a dissecting scope (see the technical floras mentioned above), but the macro differences visible in the field are quite useful. The more populations I see, the more I think Aphanes australis is introduced and A. occidentalis is native in our PNW region, in the Columbia River Gorge and along the coast in natural openings.

Lähettänyt peterzika 6 kuukautta sitten (Lippu)

I've seen both species numerous times and they are similar, but not identical. This genus in general has a more limited expression of divergence than any big flashy genus, but it's nonetheless distinction. Any botanist worth their salt should be able to recognize that, and if anything they should have been transferred to subspecies. I'm not a fan of authors who hate subdivisions, especially when it turns into lumping of distinct taxa under one contiguous heading.

I definitely would vote to revert this...

Lähettänyt silversea_starsong 6 kuukautta sitten (Lippu)

Strangely, the paper revising these genera doesn't even mention occidentalis. Is that an oversight? Or did it already consider it a synonym of arvensis due to previous literature?

Lähettänyt silversea_starsong 6 kuukautta sitten (Lippu)

There are several nuclear ribosomal DNA internal transcribed spacer (nrDNA ITS) sequences for Alchemilla arvensis, A. australis, and A. occidentalis in Genbank. I downloaded, aligned, and ran a RAxML phylogenetic analysis:
The results show that the three species are distinct, with phylogenetic structure within A. occidentalis. This is consistent with it being a native species, and contrasts with the absence of sequence variation in the other 2 species. There is also one accession of A. australis that is apparently misidentified as A. arvensis. Note that Genbank's taxonomy is inconsistent, with two of the species retained in Aphanes.

Lähettänyt aaronliston 6 kuukautta sitten (Lippu)

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