Witches' Butter

Tremella mesenterica

Description:

Tremella mesenterica (common names include the Yellow Brain, the Golden Jelly Fungus, the Yellow Trembler, and Witches' Butter) is a common jelly fungus in the Tremellaceae family of the Agaricomycotina. It is most frequently found on dead but attached and on recently fallen branches, especially of angiosperms, as a parasite of wood decay fungi in the genus Peniophora. The gelatinous, orange-yellow fruit body of the fungus, which can grow up to 7.5 cm (3.0 in) diameter, has a convoluted or lobed surface that is greasy or slimy when damp. It grows in crevices in bark, appearing during rainy weather. Within a few days after rain it dries into a thin film or shriveled mass capable of reviving after subsequent rain. This fungus occurs widely in broadleaf and mixed forests and is widely distributed in temperate and tropical regions that include Africa, Asia, Australia, Europe, North and South America. Although considered bland and flavorless, the fungus is edible. Tremella mesenterica produces carbohydrates that are attracting research interest because of their various biological activities. he species was originally described from Sweden as Helvella mesenterica by the naturalist Anders Jahan Retzius in 1769. It was later (1822) sanctioned by Elias Magnus Fries in the second volume of his Systema Mycologicum. It is the type species of the genus Tremella. Its distinctive appearance has led the species to accumulate a variety of common names, including "Witches' Butter", although this name is also applied to Exidia glandulosa. The specific epithet is a Latin adjective formed from the Ancient Greek word μεσεντεριον (mesenterion), "middle intestine," from μεσο- (meso-, "middle, center") and εντερον (enteron, "intestine"), referring to its shape. The species formerly recognized as Tremella lutescens is now seen as a form of T. mesenterica with washed-out colors and considered a synonym. Based on molecular analysis of the sequences of the D1/D2 regions of the large subunit ribosomal RNA gene and the internal transcribed spacer regions of rRNA, T. mesenterica is most closely related to T. coalescens, T. tropica, and T. brasiliensis. This analysis included 20 of the estimated 120 Tremella species. he fruit body has an irregular shape, and usually breaks through the bark of dead branches. It is up to 7.5 cm (3.0 in) broad and 2.5 to 5.0 cm (1.0 to 2.0 in) high, rounded to variously lobed or brain-like in appearance. The fruit body is gelatin-like but tough when wet, and hard when dry. The surface is usually smooth, the lobes translucent, deep yellow or bright yellow-orange, fading to pale yellow, rarely unpigmented and white or colorless. The fruit bodies dry to a dark reddish or orange. The spores, viewed in mass, are whitish or pale yellow. Although some have claimed the fungus to be inedible or merely "non-poisonous," most other sources agree that it is edible but flavorless. The gelatinous to rubbery consistency lends texture to soups. In China, the fungus is used by vegetarians to prepare "an immunomodulating cooling soup with lotus seed, lily bulbs, jujube, etc." It prefers to grow in habitats ranging from mesic to wet. The fungus grows parasitically on the mycelium of wood-rotting corticioid fungi in the genus Peniophora. Occasionally, T. mesenterica and its host fungus can be found fruiting together.

Habitat:

It prefers to grow in habitats ranging from mesic to wet. The fungus grows parasitically on the mycelium of wood-rotting corticioid fungi in the genus Peniophora. This fungus occurs widely in broadleaf and mixed forests and is widely distributed in temperate and tropical regions that include Africa, Asia, Australia, Europe, North and South America.