Tremella foliacea
Description
Tremella foliacea is a species of fungus producing brownish, frondose, gelatinous basidiocarps (fruit bodies). It is widespread, particularly in north temperate regions, and is parasitic on other species of fungi (Stereum spp.), that grow on dead attached and recently fallen branches of broadleaf trees and conifers.
When fully developed Tremella foliacea is even more contorted than its close relatives Tremella aurantia. In dry weather, these fungi shrivel to hard blackish crusts, in which state they are much more difficult to spot. When it rains the fruitbodies rehydrate and turn translucent again.
Some authorities say that this is an edible but very poor fungus, but being insubstantial it has no culinary value.
Common names: Leafy Brain, Jelly Leaf, Brown Witch's Butter.
Tremella foliacea Look-Alikes
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Parasitic on Stereum hirsutum; its fruitbodies are yellow-orange and usually less tightly folded than those of Tremella foliacea.
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Parasitic on Peniophora crust fungi, which occur on dead hardwoods, particularly oaks. Its spores are broadly ellipsoidal.
Tremella foliacea
This mushroom is variable and may represent a complex of similar species across its range. Chen (1998) described three new species in the "foliacea" group, based on microscopic differences and DNA sequencing: Tremella vasifera from Germany and T. fuscosuccinea and T. neofoliacea from Taiwan.
Tremella coffeicolor (syn. Tremella auricularia)
Originally described from Bermuda, is similar, but has larger basidia and spores. It is also known from the Azores, the Caribbean islands, and South America.
Medicinal Properties
Anti-tumor effects
Polysaccharides extracted from the mycelial culture of T. foliacea and administered intraperitoneally into white mice at a dosage of 300 mg/kg inhibited the growth of Sarcoma 180 and Ehrlich solid cancers by 60% (Ohtsuka et al., 1973).
Antibacterial activity
Brown witch’s butter was found to not produce antibacterial compounds when screened using an overlay assay (McCormack et al., 1994).
History
This jelly fungus was originally described in 1800 by Christiaan Hendrik Persoon, who called it Tremella foliacea, by which name mycologists still refer to it today.
Tremella foliacea has many synonyms including Tremella frondosa, Tremella fimbriata Pers., Gyraria foliacea (Pers.) Gray, Tremella succinea Pers., Tremella nigrescens Fr., Ulocolla foliacea (Pers.) Bref., Exidia foliacea (Pers.) P. Karst., Phaeotremella pseudofoliacea Rea, and Tremella foliacea var. succinea (Pers.) Neuhof.
Tremella, the generic name means trembling - a reference to the wobbly-jelly-like structure of fungi within this grouping. The specific epithet foliacea means folded or wrinkled like leaves.
Photo sources:
Photo 1 - Author: Ian Alexander (CC BY-SA 4.0)
Photo 2 - Author: Andrawaag (Public Domain)
Photo 3 - Author: walt sturgeon (Mycowalt) (CC BY-SA 3.0)