Basidiocarps (fruit bodies) are gelatinous and appear to be parasitic on ascomycetous fungi on wood.

[1] Molecular research, based on cladistic analysis of DNA sequences, has indicated that Sirobasidium brefeldianum may not be closely related to other Sirobasidium species, though this is based on a single culture from Europe that may be contaminated and requires further research.

[2][3] Fruit bodies are gelatinous, pustular, and whitish, typically occurring in groups.

[1] Sirobasidium brefeldianum was originally described on rotten wood, but European collections are associated with and possibly parasitic on fungi in the Diatrypaceae, including species of Eutypella, growing on dead attached or fallen wood.

[4] Sirobasidium brefeldianum has been reported not only from South America, but also Europe (Belgium, England, France, Germany), Asia (Brunei, Ceylon, India), and Macaronesia (Canary Islands), though it is not clear that all these reports refer to the same species.