''Auricularia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Auriculariaceae The Auriculariaceae are a family (biology), family of fungi in the order (biology), order Auriculariales. Species within the family were formerly referred to the "heterobasidiomycetes" or "jelly fungi", since many have gelatinous basidiocarps (fr ...

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 no ...

(fruit bodies) are typically gelatinous and ear-shaped, with a slightly downy to conspicuously hirsute upper surface and an under surface that is smooth, wrinkled or veined. All species grow on wood. Several ''Auricularia'' species are edible and commercially cultivated on a large scale in China and East Asia.

Taxonomy

The genus was first introduced in 1780 by French mycologist Pierre Bulliard for a range of different fungi producing fruit bodies with an ear-like shape. In 1822

Christian Hendrik Persoon Christiaan Hendrik Persoon (31 December 1761 – 16 November 1836) was a Cape Colony mycologist who is recognized as one of the founders of mycology, mycological Taxonomy (biology), taxonomy. Early life Persoon was born in Cape Colony at ...

restricted the genus to two gelatinous species, '' Auricularia mesenterica'' (which became the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

) and ''A. sambuci'' (a synonym of ''

Auricularia auricula-judae ''Auricularia auricula-judae'', commonly known as wood ear, jelly ear or, more historically, Jew's ear, is a species of fungus in the order Auriculariales. Basidiocarps (fruit bodies) are brown, gelatinous, and have a noticeably ear-like shap ...

''). In 1848 Swedish mycologist

Elias Magnus Fries Elias Magnus Fries (15 August 1794 – 8 February 1878) was a Swedish mycologist and botanist. He is sometimes called the Mycology, "Linnaeus of Mycology". In his works he described and assigned botanical names to hundreds of fungus and li ...

accepted ''A. mesenterica'' within the genus but, on the basis of differences in fruitbody appearance, introduced a new genus, ''Hirneola'', for most other species. This division into two genera was maintained by some authors until at least the 1960s, though American mycologist Bernard Lowy's monograph of the genus had accepted ''Hirneola'' as a synonym of ''Auricularia'' in 1952 .

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

research, based on

cladistic Cladistics ( ; from Ancient Greek 'branch') 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 ...

analysis of

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

, has shown that ''Auricularia'' (including ''Hirneola'') forms a natural,

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

grouping. It has also shown that many species are more restricted in distribution than previously thought, resulting in the description of additional new taxa.

Description

All species of ''Auricularia'' form thin, brownish, rubbery-gelatinous fruit bodies that are shelf-like or ear-shaped and up to across and thick. The fruitbodies occur singly or in clusters. The upper surface is finely

pilose Trichomes (; ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plant ...

to densely hirsute. The spore-bearing underside is smooth, wrinkled, veined, or reticulate (net-like). Unpigmented white forms are occasionally encountered.

Microscopic characters

The spore-producing

basidia A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

are tubular, laterally septate, and (in some species) up to 100

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

long. The

spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

are allantoid (sausage-shaped), and (in some species) up to 22

long. Hairs on the upper surface are thick-walled, rounded or acute at the tip, and (in some species) up to long. When sectioned, some species show a central, medulla layer of parallel

hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

, others lack such a layer.

Habitat, ecology and distribution

All species grow on wood and are

saprotrophic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ...

wood-rotters, producing a

white rot A wood-decay or xylophagous fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as ''Serpula lacrymans'', and some, such as '' Armillaria'' (honey fungus), are par ...

. Most occur on dead wood, but they can also be weakly parasitic on living wood. The majority of species grow on broadleaf trees and shrubs, but a few grow on conifers. Fruit bodies occur singly, in clusters, or in tiers. The genus has a global distribution, with some species confined to the tropics, others to north temperate regions, and others to south temperate regions.

Uses

At least three species are commercially cultivated for food on a large scale in China and East Asia. They include ''

Auricularia heimuer ''Auricularia heimuer'', also known as heimuer () or black wood ear, is a species of fungus in the order Auriculariales. It is commercially cultivated for food in China at a value exceeding $4 billion (USD) per year. The species was previously re ...

'' (black wood ear), formerly misdetermined as ''

''; ''

Auricularia cornea ''Auricularia cornea'', also known as cloud ear, is a species of fungus in the order Auriculariales. It is commercially cultivated for food in China. ''Auricularia cornea'' is a popular ingredient in many Chinese dishes and is also used in tradit ...

'' (wood ear or cloud ear), also called ''A. polytricha''; and '' Auricularia villosula''. Other species are eaten locally around the world. A study on the use of fungi by the

Bini people The Edo people, also referred to as the Benin people, are an Edoid-speaking ethnic group. They are prominently native to seven southern local government areas of Edo State, Nigeria. They are speakers of the Edo language and are the descendants ...

of southern

Nigeria Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, ...

found that the local inhabitants collected and ate a species similar to ''A. auricula-judae'', but that it was not one of the fungi they used medicinally. Collection of ''Auricularia'' species has also been documented in

Nepal Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia. It is mainly situated in the Himalayas, but also includes parts of the Indo-Gangetic Plain. It borders the Tibet Autonomous Region of China Ch ...

. However, the Nepalese do not consider them all that good for eating; of the three grades given to edible fungi, they were given the worst. Additional places where ''Auricularia'' species have been recorded as locally gathered and consumed include Benin, Chile, Fiji, Ghana, Guatemala, India, Indonesia, Madagascar, Mexico, Mozambique, and Poland. Several species, including the Asian cultivated species and the European ''A. auricula-judae'' (jelly ear or jew's ear), have been used in traditional medicine. They have also been investigated for potential pharmaceutical use.

Species

References

{{Authority control Auriculariales Agaricomycetes genera