Summary:
Tremella lethariae produces minute fruitbodies inducing gall formation. It is convex, colored like the thallus or brownish, becoming orange brown when mature. It is identified by microscopic characters including 2-4-celled, non-stalked basidia.

Microscopic:
spores 6-8 x 5.5-7.5 microns, elliptic to nearly round, with a distinct apiculus; basidia 4-spored, when mature with longitudinal septa, 15-20 x 10-16 microns, epibasidia subcylindric, at least 30 microns long, 2-4.5 microns wide; hymenium containing numerous probasidia, probasidial initials subspherical, clamp connections not observed; hyphidia and cystidia absent; fertile hyphae 3.5-4.5 microns in diameter, clamp connections not observed; anamorph unknown, (Diederich(1)), 2-4-spored basidia, with basal clamp connection (Diederich(2))

Notes:
Tremella lethariae is found in BC and CA .

Synonyms and Alternate Names:
Cyphella alboviolascens (Alb. & Schwein.) P. Karst
Cyphella pezizoides Zopf