Infected shoots scattered, pale all over (greenish to pinkish white) with glabrous elongated internodes and only indistinctly set-off leaf-pairs. Leaves malformed (up to 6 x 3 mm), mostly subcylindric, spreading, like the stem eventually hymenium-clad, but apical or marginal parts (especially of the lower leaves) not rarely of normal shape, structure and colour and remaining hymenium-less ...

In Fennoscandia ... very common on C. tetragona, occurs mostly together with E. hypogenum and seems to be the more abundant of them ...

it seems justified to combine this tetragona parasite with E. cassiopes, originally described on C. mertensia ...

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