A fungal rust infection on a Viola species.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
Lovely recent posts Steve. Excellent diagnostic pictures and easy-going ID Notes.
I've agreed - after a real blast on the Internet.
Excellent lookalikes here http://eol.org/pages/1029845/media
Good diagnostic pictures, features well shown.
Rusts usually have different stages in their life cycles.
Shown here is the aecial ("cluster-cup") stage, producing the rather thick-walled spores that in many rusts (but not this one) allow transmission to an alternate host. Later in the year come the dark brown, powdery spots of the telial stage of the rust, still on Viola species. The telial stage looks very different from what we see here.
Lat/Lng: 51.329907748892, -0.75174808502197
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