The Agaricomycetes are a class of fungi in the division Basidiomycota. The taxon is roughly identical to that defined for the Homobasidiomycetes by Hibbett & Thorn, with the inclusion of Auriculariales and Sebacinales. It includes not only mushroom-forming fungi, but also most species placed in the deprecated taxa Gasteromycetes and Homobasidiomycetes. Within the subdivision Agaricomycotina, which already excludes the smut and rust fungi, the Agaricomycetes can be further defined by the exclusion of the classes Tremellomycetes and Dacrymycetes, which are generally considered to be jelly fungi. However, a few former "jelly fungi", such as Auricularia, are classified in the Agaricomycetes. According to a 2008 estimate, Agaricomycetes include 17 orders, 100 families, 1147 genera, and about 21000 species. Modern molecular phylogenetic analyses have been since used to help define several new orders in the Agaricomycetes: Amylocorticiales, Jaapiales, Stereopsidales, and Lepidostromatales.
Agaricomycotina is one of three subdivisions of the Basidiomycota, and represents all of the fungi which form macroscopic fruiting bodies. Agaricomycotina contains over 30,000 species, divided into three classes: Tremellomycetes, Dacrymycetes, and Agaricomycetes. Around 98% of the species are in the class Agaricomycetes, including all the agarics, bracket fungi, clavarioid fungi, corticioid fungi, and gasteroid fungi. Tremellomycetes contains many basidiomycete yeasts and some conspicuous jelly fungi. Dacrymycetes contains a further group of jelly fungi. These taxa are founded on molecular research, based on cladistic analysis of DNA sequences, and supersede earlier morphology-based classifications. Agaricomycotina contains nearly one third of all described species of fungi.
The Tremellaceae are a family of fungi in the order Tremellales. The family is cosmopolitan and contains both teleomorphic and anamorphic species, most of the latter being yeasts. All teleomorphs in the Tremellaceae are parasites of other fungi, though the yeast states are widespread and not restricted to hosts. Basidiocarps, when produced, are gelatinous.
The Cystofilobasidiales are an order of fungi in the class Tremellomycetes of the Basidiomycota. They usually exhibit a life phase of free-living yeasts. The order contains two families with seven genera and some 25 species.
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 teleomorphic species in the Tremellales are parasites of other fungi, though the yeast states are widespread and not restricted to hosts. Basidiocarps, when produced, are gelatinous.
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, when produced, are gelatinous and are colloquially classed among the "jelly fungi". Over 100 species of Tremella are currently recognized worldwide. One species, Tremella fuciformis, is commercially cultivated for food.
The Agaricostilbomycetes are a class of fungi in the subdivision Pucciniomycotina of the Basidiomycota. The class consists of a single order, six families, and 15 genera. Its type genus, Agaricostilbum was originally placed in Ascomycota, and later, Agaricomycotina, before being placed in Pucinniomycotina.
The Filobasidiaceae are a family of fungi in the order Filobasidiales. Most species are yeasts, but some form gelatinous fruit bodies that are parasitic on other fungi, including lichens. The family currently contains five genera.
Kwoniella is a genus of fungi in the family Cryptococcaceae. The genus originally contained the single species Kwoniella mangrovensis, found in the Florida Everglades and The Bahamas. Molecular research, based on cladistic analysis of DNA sequences, has however, now extended the genus to eleven species, most known only from their yeast states.
The Agaricostilbales are an order of fungi in the class Agaricostilbomycetes. The order consists of six families and 15 genera.
Phaeotremella is a genus of fungi in the family Phaeotremellaceae. All Phaeotremella species are parasites of other fungi and produce anamorphic yeast states. Basidiocarps, when produced, are gelatinous and are colloquially classed among the "jelly fungi". Fifteen or so species of Phaeotremella are currently recognized worldwide. Tremella sanguinea, shown to be a Phaeotremella species by DNA sequencing, is cultivated in China as an ingredient in traditional Chinese medicine.
Phaeotremella foliacea is a species of fungus in the family Phaeotremellaceae. It produces brownish, frondose, gelatinous basidiocarps and is parasitic on the mycelium of Stereum sanguinolentum, a fungus that grows on dead attached and recently fallen branches of conifers. It is widespread in north temperate 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.
The Holtermanniales are an order in the fungal class Tremellomycetes. The order contains two genera. Species of Holtermannia produce groups of horn-like gelatinous basidiocarps on wood and have associated yeast states. Species of Holtermaniella are only known as yeasts.
Pseudotremella is a genus of fungi in the family Bulleraceae. All Pseudotremella species are parasites of other fungi and produce anamorphic yeast states. Basidiocarps, when produced, are gelatinous and are colloquially classed among the "jelly fungi". Four species of Pseudotremella are currently recognized worldwide. Two of these species are, as yet, only known from their yeast states.
Solicoccozyma is a genus of fungi in the family Piskurozymaceae. Species have only been isolated in their yeast states, several of which were formerly referred to the genus Cryptococcus, but can produce filamentous states with basidia in culture. Nine species have been described worldwide.
The Rhynchogastremaceae are a family of fungi in the order Tremellales. The family currently contains two genera. Some species produce filamentous sexual states with septate basidia and are parasites of other fungi. Most, however, are only known from their yeast states.
The Trimorphomycetaceae are a family of fungi in the order Tremellales. The family currently contains four genera. Some species produce filamentous sexual states and are parasites of other fungi. Most, however, are only known from their yeast states.
The Trichosporonaceae are a family of fungi in the order Trichosporonales. The family currently contains six genera. Species are not known to produce basidiocarps, but exist as yeasts or produce septate hyphae with arthroconidia. Several species are human pathogens.
The Tetragoniomycetaceae are a family of fungi in the order Trichosporonales. The family currently contains four genera. Several species are only known from their yeast states.
Tremella yokohamensis is a species of fungus in the family Tremellaceae. It produces white, foliaceous, gelatinous basidiocarps and is parasitic on other fungi on dead wood of broad-leaved trees. It was originally described from Japan.
