Exidia Recisa: The Ultimate Mushroom Guide

About The Exidia Recisa Mushroom

The name Jelly Roll (Exidia recisa or Exidia crenata) conjures up images of homemade pastries with jelly and sugar, but once you see a picture of this fungus you’ll see the humor in the name. A very unsightly fungus to say the least, but Amber, Black, or Brown Jelly Roll is in the group of fungus called jelly fungus or cup fungus, another common name for these species is witch’s butter.

A very common fungus, they have a gelatinous texture, but the vast majority of them are edible, some are prized in certain parts of the world. This species is found growing on recently dead hardwoods.

It is rather tasteless with a gelatinous texture but absorbs easily the flavors it is cooked with. You can eat them raw or cooked. They are used in salads and soups. They are also very commonly seen and make for a good snack when you’re in the mood for something a little different.

Other names: Willow Brain, Amber Jelly Roll.

Exidia Recisa Identification

1. Ecology

   Saprobic; growing on recently fallen hardwood sticks and branches (especially on the wood of oaks); spring through fall; widely distributed in North America, but much more common east of the Rocky Mountains.

2. Fruiting Body

   Individual fruiting bodies are 1–4 cm across, but are typically clustered together to appear as a larger mass; gelatinous but fairly firm; lobed, with concave depressions separated by ridges; usually featuring a small pseudostem—or at least attached more or less centrally at a pinched point; dark brown, often with a purplish cast; bald; undersurface dull brown; blackening along the edges and ridges when dried out.

3. Spore Print

   White.

4. Microscopic Features

   Spores 10–17 x 2.5–4 µm; allantoid; smooth; hyaline in KOH. Basidia to about 15 x 8 µm; pyriform to subglobose; developing a longitudinal septum and long, fingerlike sterigmata. Hyphae 2–4 µm wide; often gelatinized; septate; clamped.

Exidia Recisa Taxonomy

The species was originally found growing on willow in Germany and was described in 1813 by L.P.F. Ditmar as Tremella recisa. It was transferred to the genus Exidia by Fries in 1822. Tremella salicum (the epithet means "of willow") has long been considered a synonym.

The epithet "recisa" means "cut-off", with reference to the shape of the fruit bodies.