When I put the first photo into iNat (as you do) I was immediately asked to confirm it was Heracleum sphondylium, It is, but where is the fun in that?
But it shows how well AI is working. Another year and iSpot will be out of business - do you hear?.
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Anyway, look closely (as you should) and it is stained yellow. Why pass it by?
I turned over a leaf, photos 2&3. If you are not interested just click next.
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And so, 2 hours later I have a decent photo record of Puccinia heraclii
Try finding it on the webthing.
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There were no other Obs of this in iNat and none here either.
Oh, and check the Gallery in GBIF (In the ID Panel) impressed?
Don't bother with Wiki nor EoL and NBN is too long winded
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I have it at home under a glass bell (er basin) but it was extensive, though very localised, at the location - perhaps two plants.
I am left wondering if it will survive and develop until the plant is a metre high.
Habitat looks a bit uninspiring but hey it's not all sea, standing stones and fudge here!.
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I have 20 photos, of course. So I will form another Observation in a couple of days so that there ARE Other Observations!
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see this https://www.gbif.org/occurrence/3859036106
and
https://bladmineerders.nl/parasites/fungi/basidiomycota/pucciniomycotina/pucciniales/pucciniaceae/puccinia/puccinia-heraclei/
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Edit 2023 - added the sub habitat tags