Coleosporium tussilaginis/ Campanula persicifolia ?

[BubikolRamios]

Host, fresh stem of Campanula persicifolia. Coleosporium tussilaginis on my list of possible guests, but other than that ...
Three such spots in total.
EDIT: Uredo campanulae/Coleosporium campanulae seems nice ... ?

[abeja]

Hi,
Uredinia of Coleosporium campanulae should be a match.

https://bladmineerders.nl/en/parasites/ ... ampanulae/

The uredinia and telia of Coleosporium species morphologically are indistinguishable. For pictures see for instance C. melampyri and C. tussilaginis.

I had a look into the book "Faszinierende Pflanzenpilze" (Julia Kruse = Phytojule, here)
She writes in *Campanula* (translated with DeepL):

Coleosporium campanulae, Rust fungus
On the underside of conspicuous, yellow leaf spots, approximately 1–2 mm in size and mostly angular, there are orange to yellow, flat, cushion-shaped uredinia, which are initially covered by a blister-like layer of epidermis and often arranged in a ring.
Telia are usually found on the underside of the leaves as firm, crusty, bright red-orange, and shiny clusters that are permanently covered by the epidermis.
In the spring, spermogonia and aecia form on the needles of pine trees.

I am wondering a bit about spots on the stem only. (Stems are not mentioned.)
Nothing at all on the underside of the leaves? Maybe it’s “not yet”.

https://bladmineerders.nl/en/host-plant ... sicifolia/
mentions additionally Puccinia campanulae, but it produces only telia (which should look different).