Ramularia digitalis-ambiguae
Anamorph: mycelium immersed. Conidiophores in clusters emrging from stomata, hyaline, thin-walled, smooth, 1- to 2-septate, ± cylindrical, straight to sinuous, unbranched, sometimes reduced to conidiogenous cells. Conidiogenous cells (5–) 14–19 (–29) × 1.5–2 (–3) μm, with 1–3 conidiogenous loci. Loci almost flat to cylindrical-protuberant, thickened, darkened and refractive. Conidia 8-15 (-17) x 3-4.5 µm. Intercalary conidia usually longer than terminal conidia, irregularly cylindrical, hyaline, thin-walled, smooth to slightly verruculose, catenate, the hila thickened, darkened and refractive. Terminal conidia cylindric-ellipsoidal to ellipsoidal-fusiform or slightly ovoid.
Teleomorph: reported to be Mycosphaerella mariae (Sacc. & E. Bommer) Lindau fide Videira et al. (2015).
Common and widespread; very unlikely to be threatened.
Until recently referred to as Ramularia variabilis, but that is a morphologically near-identical but phylogenetically quite distinct species that is a parasite of Verbascum.
On living leaves of Digitalis purpurea, causing spotting.
Throughout the British Isles.