E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Exobasidium dimorphosporum is distinguished from Exobasidium vaccinii-uliginosi by the spores which are dimorphic [with two shapes] and frequently septate - the broad spores are somewhat too short and the narrow ones are too narrow and too long for E. vaccinii-uliginosi.

The type was collected on Vaccinium caespitosum in BC. (Savile 1959).

Fruiting body:
similar to Exobasidium vaccinii-uliginosi in morphology and habit but distinguished by spores

Microscopic:
spores of two forms: either 13.0-18.5 x 6.5-8.5 with inconspicuous hilum or 18.5-28.5(32.0) x 5.0-7.0(8.0) microns with hooked hilum, 0(1)-septate; basidia 2-spored or rarely 3-spored, projecting 26-40 microns beyond the cuticle, 5.0-9.5 microns wide; conidia not seen