Tremella exigua
Tremella exigua is a small, jelly-like fungus in the Tremellaceae family. It forms olive-black, gelatinous fruit bodies up to about 8 mm across, sometimes looking brain‑like as they mature. It parasitizes other fungi that grow on dead wood, especially species in the Diaporthe and Cucurbitaria groups.
The species was first described from a dead ash branch in France. It has several older names that are now considered synonyms or not valid, such as Tremella atrovirens and Tremella genistae.
Genetic studies suggest Tremella exigua is not closely related to the main Tremella group and may belong to a different genus in the Bulleraceae family.
Tremella exigua is found mainly in Europe, with reports also from Canada and Ecuador. It is often found on dead branches of gorse, broom, and barberry, in addition to ash.
This page was last edited on 3 February 2026, at 06:23 (CET).