I think this is a gall rather than a fungus but not sure so am posting as "invert"
No identification made yet.
No interactions present.
If you are not sure what it is, I think you should wait before doing an Interaction. Interactions ought to be used only for 100% certainty, I would have thought...otherwise it is rather poor science.
My Flickr photos...
I am not sure it is "poor science" to suggest an interaction even if the identity of one (or both) is not yet certain. My aim was to put the identification into two areas. For some groups (leaf miners, galls and fungi) the host plant is essential for identification. The fact that names of two species of an "interaction" are known does not mean that the interaction is what is described. An known insect may observed visiting a known plant and so be described as a pollinator - but without evidence that cross fertilisation takes place it may not be so
If the two species involved end up being correctly identified, then fair enough. But if they don't, the interaction will still show up on search engines like Google, and so be in the public domain. That to me is one reason why Interactions should not be put up without certainty, as people might stumble upon it and then repeat the unconfirmed interaction. The internet is overflowing with misidentifications...I don't think that a site like iSpot should be adding to that.
At the same time, I do really like your photos and the discussion, so nothing personal intended!
Yes Mark and Ian, I am continuing to hate the Iteractions idea. It is becoming common to post the same picture three times to try to serve its purpose.
It is already showing in Google. I fear it will not get much support Mark until you offer a gentler ID - say Infected Elder Leaf and remove the association/interaction (for now)
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