''Auricularia americana'' 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

Auriculariaceae The Auriculariaceae are a family of fungi in the order Auriculariales. Species within the family were formerly referred to the "heterobasidiomycetes" or "jelly fungi", since many have gelatinous basidiocarps (fruit bodies) that produce spores on ...

Basidiocarp 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 ...

s (fruitbodies} are gelatinous, ear-like, and grow on dead

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

wood. The species was formerly confused with ''

Auricularia auricula-judae ''Auricularia auricula-judae'', which has the recommended English name jelly ear, also known as Judas’s ear or Jew’s ear, is a species of fungus in the order Auriculariales. Basidiocarps (fruit bodies) are brown, gelatinous, and have a noti ...

'', which grows on broadleaf wood and is confined to Europe.

Taxonomy

The species was originally described in 1987 from

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

on ''

Abies balsamea ''Abies balsamea'' or balsam fir is a North American fir, native to most of eastern and central Canada (Newfoundland west to central Alberta) and the northeastern United States (Minnesota east to Maine, and south in the Appalachian Mountains to ...

'', but was not validly published until 2003.

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

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 usua ...

, has shown that ''Auricularia americana'' is a distinct species.

Description

''Auricularia americana'' forms thin, brown, rubbery-gelatinous fruit bodies that are 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 pl ...

. The spore-bearing underside is smooth.

Microscopic characters

The microscopic characters are typical of the genus ''

Auricularia ''Auricularia'' is a genus of fungi in the family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maint ...

''. 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 tubular, laterally septate, 55–70 × 4–5 µm. The

spores In biology, a spore is a unit of sexual 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 plants, algae, f ...

are allantoid (sausage-shaped), 14–16.5 × 4.5–5.5 µm.

Habitat and distribution

''Auricularia americana'' is a wood-rotting species, typically found on dead attached or fallen wood of conifers. It is widely distributed in North America and is also known from China and the

Russian Far East The Russian Far East (russian: Дальний Восток России, r=Dal'niy Vostok Rossii, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in Northeast Asia. It is the easternmost part of Russia and the Asian continent; and is admini ...

Similar species

In North America, ''

Auricularia angiospermarum ''Auricularia angiospermarum'' (wood ear or tree ear) is a species of fungus in the family Auriculariaceae. Basidiocarps (fruitbodies) are gelatinous, ear-like, and grow on dead wood of broadleaf trees. It is a North American species and was for ...

'' is almost identical but grows on the wood of broadleaf trees. No other North American ''Auricularia'' species grows on conifer wood. In China and Tibet, however, a second species, ''Auricularia tibetica'', also occurs on conifers. It can be distinguished microscopically by its longer

and larger

basidiospores A basidiospore is a reproductive spore produced by Basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are pro ...

References

{{Taxonbar, from=Q10422714 Auriculariales Fungi of North America Fungi of China