Infected shoots scattered, slightly elongated with distinct, sparsely hairy internodes. Leaves much enlarged (up to 10 x 6 mm.), triangular with distinct, hastate base, soft, thin and flat with revolute margin, spreading or slightly reflexed (never appressed), blood-red or whitish (very rarely pink) above (color depending on the host-individual ... ), eventually hymenium-clad beneath.

- Nannfeldt, J.A.: (1981) Exobasidium, a taxonomic reassessment applied to the European species^©