Pucciniastrum epilobii
Spermogonia hypophyllous, abundant, ca 100 µm diam. and 25 µm high, hemispherical with the central part flattened, subcuticular. Spermogonia 1.5-3 µm in length, ovoid.
Aecia hypophyllous, usually in two rows, cylindrical, ca 250 µm diam. and 1 mm high, whitish, splitting above or rarely at the sides, soon breaking down. Peridium composed of vertically elongate polyhedral cells 25-42 x 10-16 µm in size, the outer wall smooth and the inner wall minutely verrucose. Aeciospores 14-21 x 10-14 µm, subglobose, ellipsoidal or ovoid, the wall 1-1.5 µm thick, the wall minutely verrucose with a smooth spot on one side.
Uredinia mostly hypophyllous or on stems, scattered or in groups, 100-250 µm diam., ± hemispherical, eventually opening with an apical pore, yellowish, the upper wall breaking down to reveal the pulverulent contents. Peridium rather thin, composed of angular thick-walled cells 10-18 µm in diam. Urediniospores 15-23 x 10-15 µm, ovoid or ellipsoidal, the wall 1-1.5 µm thick, hyaline, remotely and shortly echinulate.
Telia hypophyllous, rarely epiphyllous or on stems, 100-200 µm diam., mostly in groups, subepidermal, pale brown. Teliospores intercellular, 2- or 4-celled, the 2-celled spores 18-28 x 7-15 µm and the 4-celled spores 20-30 µm diam., the lateral wall 1-1.5 µm thick, to ca 3 µm at the apex, brown, smooth, with a single pore towards the apex.
Not formally assessed on a national basis, but the species is common and widespread and would surely be considered as of Least Concern. In Wales it was assessed as of Least Concern by Woods et al. (2015).
Spermogonia and aecia form on leaves of Abies grandis; these morphs appear very restricted in distribution. Uredinia and telia occur on many Epilobium species, especially E. angustifolium, E. montanum and E. palustre; also on cultivated Fuchsia species.
There is only a single record of aecia in FRDBI, from Scotland (VC91 Kincardine). Uredinia and telia are widespread, being reported from all parts of Great Britain north to Inverness-shire, also from ROI and Northern Ireland.