''Phaeotremella foliacea'' (synonym ''Tremella foliacea'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Phaeotremellaceae The Phaeotremellaceae are a family of fungi in the order Tremellales The Tremellales are an order of fungi in the class Tremellomycetes. The order contains both teleomorphic and anamorphic species, most of the latter being yeasts. All teleomo ...

. It produces brownish,

frondose Frondosity (from Latin ''frondōsus'' meaning 'leafy') is the property of an organism that normally flourishes with fronds or leaf-like structures. Many frondose organisms are thalloid and lack the organization of tissues into organs, with the ...

, gelatinous

basidiocarps In fungi, a basidiocarp, basidiome, or basidioma () is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not ...

(fruit bodies) and is

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...

on the

mycelium Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates ...

of '' Stereum sanguinolentum'', a fungus that grows on dead attached and recently fallen branches of conifers. It is widespread in north

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

regions. In the UK it has the recommended English name leafy brain and has also been called jelly leaf and brown witch's butter. Prior to 2017, the name ''Tremella foliacea'' was also applied to similar-looking species on broadleaf trees, now distinguished as '' Phaeotremella frondosa'' and ''Phaeotremella fimbriata''.

Taxonomy

''Tremella foliacea'' was first published in 1800 by South African-born mycologist Christiaan Hendrik Persoon. The name remained in use until molecular research, based on

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

analysis of

DNA sequences A nucleic acid sequence is a succession of bases signified by a series of a set of five different letters that indicate the order of nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. By convention, sequences are us ...

, showed that ''Tremella foliacea'' was not closely related to the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

of ''

Tremella ''Tremella'' is a genus of fungi in the family Tremellaceae. All ''Tremella'' species are parasites of other fungi and most produce anamorphic yeast states. Basidiocarps (fruit bodies), when produced, are gelatinous and are colloquially classed ...

'' but belonged in a separate genus, ''

Phaeotremella ''Phaeotremella'' is a genus of fungi in the family Phaeotremellaceae. All ''Phaeotremella'' species are parasites of other fungi and produce anamorphic yeast states. Basidiocarps (fruit bodies), when produced, are gelatinous and are colloquial ...

''. Further research revealed that the name ''Tremella foliacea'' covered several similar but distinct species, the name ''Phaeotremella foliacea'' being restricted to the fungus growing on conifers. The

epithet An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...

"foliacea" means "leafy", with reference to the shape of the fruit bodies. Herman Phaff and L. do Carmo Sousa described the

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

''Cryptococcus skinneri'' in 1962 from the

frass Frass refers loosely to the more or less solid excreta of insects, and to certain other related matter. Definition and etymology ''Frass'' is an informal term and accordingly it is variously used and variously defined. It is derived from the ...

of the beetle ''Scolytus tsugae'' feeding on Western Hemlock (''

Tsuga heterophylla ''Tsuga heterophylla'', the western hemlock or western hemlock-spruce, is a species of hemlock native to the west coast of North America, with its northwestern limit on the Kenai Peninsula, Alaska, and its southeastern limit in northern Sonom ...

''). DNA sequencing has shown that this is the yeast state of ''Phaeotremella foliacea''.

Description

Fruit bodies are gelatinous, brown to dark brown, up to 5 cm (2 in) across, and seaweed-like (with branched, undulating fronds). Microscopically, the hyphae are clamped and occur in a dense gelatinous matrix. Haustorial cells arise on the hyphae, producing filaments that attach to and penetrate the hyphae of the host. The

basidia A basidium () is a microscopic sporangium (a spore-producing structure) found on the hymenophore of fruiting bodies of basidiomycete fungi which are also called tertiary mycelium, developed from secondary mycelium. Tertiary mycelium is highly-c ...

are tremelloid (globose to ellipsoid, with oblique to vertical septa), 12 to 18 by 10 to 14 μm, usually unstalked. The basidiospores are mostly ellipsoid, smooth, 5.5 to 9.5 by 4.5 to 8.5 μm, and germinate by hyphal tube or by

cells.

Similar species

'' Phaeotremella frondosa'' is a common and widespread species parasitizing ''

Stereum ''Stereum'' is the type genus of the Stereaceae family of fungi, in the Russulales order. Until recently, the genus was classified in the Corticiaceae family, of the Corticiales order. However, it was given its own family as a result of the spl ...

'' species on broadleaf trees. It often produces larger and paler fruit bodies than ''Phaeotremella foliacea''. ''Phaeotremella fimbriata'' is a European species parasitizing '' Stereum rugosum'' on broadleaf trees. Its fruitbodies are comparatively small and dark brown to black. ''Phaeotremella eugeniae'' is its temperate Asian counterpart.

Habitat and distribution

''Phaeotremella foliacea'' is a parasite of '' Stereum sanguinolentum'', growing on the host's hyphae in the wood rather than on the host's fruit bodies. Following its hosts, fruit bodies of ''P. foliacea'' are typically found on dead, attached or recently fallen branches of conifers. The species is known from North America, Europe, and northern Asia.

References

External links

* {{Taxonbar, from=Q882168 Tremellomycetes Fungi described in 1800 Fungi of Asia Fungi of Europe Fungi of North America Taxa named by Christiaan Hendrik Persoon