''Pleurotus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

mushroom A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans. The standard for the name "mushroom" is t ...

s which includes one of the most widely eaten mushrooms, '' P. ostreatus''. Species of ''Pleurotus'' may be called oyster, abalone, or tree mushrooms, and are some of the most commonly cultivated

edible mushroom Edible mushrooms are the fleshy and edible fruit bodies of several species of macrofungi (fungi which bear fruiting structures that are large enough to be seen with the naked eye). They can appear either below ground (hypogeous) or above ground ...

s in the world. ''Pleurotus'' fungi have also been used in mycoremediation of pollutants, such as

petroleum Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name ''petroleum'' covers both naturally occurring unprocessed crud ...

and polycyclic aromatic hydrocarbons.

Etymology

The genus name ''Pleurotus'' literally means ''side ear'' in reference to the mushroom caps being laterally attached to the substrate. It is a composite of the Ancient Greek words : pleurá - ''side'', and the stem ''-oto'' referring to ears (from , ὠτός : ''ear'').

Description

The caps may be laterally attached (with no stipe). If there is a stipe, it is normally eccentric and the gills are decurrent along it. The term '' pleurotoid'' is used for any mushroom with this general shape. The spores are smooth and elongated (described as "cylindrical"). Where

hypha 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 or ...

e meet, they are joined by clamp connections. ''Pleurotus'' is not considered to be a bracket fungus, and most of the species are

monomitic 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 or ...

(with a soft consistency). However, remarkably, ''

Pleurotus dryinus ''Pleurotus dryinus'' is a species of fungus in the family Pleurotaceae. It grows on dead wood and is also a weak pathogen; infecting especially broad-leaved trees. Naming The species name is a Latinised version of the Greek word "dryinos" (δ� ...

'' can sometimes be

dimitic 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 or ...

, meaning that it has additional skeletal hyphae, which give it a tougher consistency like bracket fungi.

Ecology

''Pleurotus'' fungi are found in both

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

and

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 ...

climates throughout the world. Most species of ''Pleurotus'' are white-rot fungi on

hardwood Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from ...

trees, although some also decay conifer wood. ''

Pleurotus eryngii ''Pleurotus eryngii'' (also known as king trumpet mushroom, French horn mushroom, eryngi, king oyster mushroom, king brown mushroom, boletus of the steppes, trumpet royale, aliʻi oyster) is an edible mushroom native to Mediterranean regions of ...

'' is unusual in being a weak parasite of

herbaceous plant Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

s, and ''P. tuber-regium'' produces underground sclerotia. In addition to being saprotrophic, all species of ''Pleurotus'' are also nematophagous, catching

nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

s by paralyzing them with a toxin.

Cuisine

Oyster mushrooms are popular for cooking, torn up instead of sliced, especially in

stir fry Stir frying () is a cooking technique in which ingredients are fried in a small amount of very hot oil while being stirred or tossed in a wok. The technique originated in China and in recent centuries has spread into other parts of Asia and t ...

or sauté, because they are consistently thin, and so will cook more evenly than uncut mushrooms of other types. They are often used in

vegetarian cuisine Vegetarian cuisine is based on food that meets vegetarian standards by not including meat and animal tissue products (such as gelatin or animal-derived rennet). Lacto-ovo vegetarianism (the most common type of vegetarianism in the Western world) ...

Taxonomy

The classification of species within the genus ''Pleurotus'' is difficult due to high

phenotypic In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...

variability across wide geographic ranges, geographic overlap of species, and ongoing evolution and

speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...

. Early

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

efforts placed the oyster mushrooms within a very broad '' Agaricus'' as ''Agaricus ostreatus'' (

Jacq. Nikolaus Joseph Freiherr von Jacquin (16 February 172726 October 1817) was a scientist who studied medicine, chemistry and botany. Biography Born in Leiden in the Netherlands, he studied medicine at Leiden University, then moved first to Par ...

1774). Paul Kummer defined the genus ''Pleurotus'' in 1871; since then, the genus has been narrowed with some species reclassified to other genera, such as ''

Favolaschia ''Favolaschia'' is a genus of fungi in the family Mycenaceae. The genus has a widespread distribution, and contains about 50 species. Like the genus Favolus, the name is derived from the Latin ''favus'' meaning ''honeycomb'', as the fungi with t ...

'', ''

Hohenbuehelia ''Hohenbuehelia'' is a pleurotoid genus of agaric fungi characterized by gelatinous-sheathed bowling-pin-shaped cystidia, on conidia, basidiospore germ tubes, and mycelium that adhere to and capture nematodes. The fruitbodies bear thick-walled cy ...

'', '' Lentinus'', ''

Marasmiellus ''Marasmiellus'' is a genus of fungi in the family Omphalotaceae (synonym to Marasmiaceae). The widespread genus, circumscribed by American mycologist William Murrill in 1915, contains over 250 species. The name comes from the Greek '' marasmus'' ...

'', '' Omphalotus'', ''

Panellus ''Panellus'' is a genus of more than 50 mushroom species of fungi in the family Mycenaceae as defined molecularly. Prior to molecular analyses the generic name had been used for any white-spored '' pleurotoid'' with amyloid spores. Unrelated but ...

'', ''

Pleurocybella ''Pleurocybella'' is a genus of fungus in the family Phyllotopsidaceae The Phyllotopsidaceae are a family of fungi in the order Agaricales. Basidiocarps are either clavarioid and simple (in the genus ''Macrotyphula'') or agaricoid and cluste ...

'', and ''

Resupinatus ''Resupinatus'' is a genus of fungi in the family Tricholomataceae. Species are saprobic, and often found growing on the underside of decaying wood or sides of decaying woody substrates. The generic name is derived from the Latin ''resupinus'' (b ...

''. See Singer (1986) for an example of ''Pleurotus''

taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

based on morphological characteristics.

Phylogeny

More recently, molecular

phylogenetics In biology, phylogenetics (; from Greek language, Greek wikt:φυλή, φυλή/wikt:φῦλον, φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary his ...

has been utilized to determine genetics, genetic and

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

ary relationships between groups within the genus, delineating discrete

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

s. ''Pleurotus'', along with the closely related genus ''

'', has been shown to be

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

. Tests of cross-breeding viability between groups have been used to further define which groups are deserving of

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 ...

rank, as opposed to

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

, variety, or synonymy. If two groups of morphologically distinct ''Pleurotus'' fungi are able to

cross-breed A crossbreed is an organism with purebred parents of two different breeds, varieties, or populations. ''Crossbreeding'', sometimes called "designer crossbreeding", is the process of breeding such an organism, While crossbreeding is used to main ...

and produce fertile offspring, they meet one definition of

. These reproductively discrete groups, referred to as intersterility groups, have begun to be defined in ''Pleurotus''. Many binomial names used in literature are now being grouped together as species complexes using this technique, and may change.

Phylogenetic species

The following species list is organized according to 1. phylogenetic clade, 2. intersterility group (group number in

Roman numerals Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, eac ...

) or sub-clade, and then 3. any older binomial names that have been found to be closely related, reproductively compatible, or synonymous, although they may no longer be taxonomically valid. This list is likely to be incomplete. Pleurotus populinus 13996

* ''P. ostreatus'' clade ** I. '' P. ostreatus'' (oyster or pearl oyster mushroom) – North America and northern Eurasia *** '' P. florida'' ** II. '' P. pulmonarius'' (phoenix or Indian oyster mushroom) – North America, Eurasia, and Australasia *** '' P. columbinus'' *** '' P. sapidus'' ** III. '' P. populinus'' – North America ** VI. '' P. eryngii'' (king oyster mushroom) – Europe and the Middle East *** '' P. ferulae'' *** '' P. fossulatus'' – Afghanistan *** '' P. nebrodensis'' ** XII. '' P. abieticola'' – Asia ** XIII. '' P. albidus'' – Caribbean, Central America, South America *''P. djamor-cornucopiae'' clade Spanish-mushrooms

** IV. '' P. cornucopiae'' (branched oyster mushroom) – Europe *** '' P. citrinopileatus'' (golden oyster mushroom) – eastern Asia *** '' P. euosmus'' (tarragon oyster mushroom) ** V. '' P. djamor'' (pink oyster mushroom) – pantropical *** '' P. flabellatus'' *** '' P. salmoneo-stramineus'' *** '' P. salmonicolor'' ** XI. '' P. opuntiae'' – North America, New Zealand ** XVI. '' P. calyptratus'' * ''P. cystidiosus'' clade Limonenseitlinge (Pleurotus citrinopileatus) - 20100828

Limonenseitlinge (Pleurotus citrinopileatus) - 20100828

** VII. '' P. cystidiosus'' (abalone mushroom) – global *** '' P. abalonus'' – Taiwan *** '' P. fuscosquamulosus'' – Africa, Europe *** '' P. smithii'' – Mexico ** IX. '' P. dryinus'' – North America, Europe, and New Zealand * VIII. ''

Lentinus levis ''Lentinus levis'' is a species of edible fungus in the family Polyporaceae. It was described by Miles Joseph Berkeley and Moses Ashley Curtis in 1853 and given its current name in 1915 by William Murrill. As a saprotroph, it can be cultivated. ...

'' – subtropical to tropical, moved to genus ''Lentinus''. * X. '' P. tuber-regium'' (king tuber mushroom) – Africa, Asia, Australasia * XIV. '' P. australis'' (brown oyster mushroom) – Australia and New Zealand * XV. '' P. purpureo-olivaceus'' – Australia and New Zealand ** '' P. rattenburyi''

'' Incertae sedis'' species

* '' P. parsonsii'' * '' P. velatus''

Former species

* '' P. gardneri'' was reclassified to the genus ''

Neonothopanus ''Neonothopanus'' is a genus of three species of fungi in the agaric family Marasmiaceae. The genus was circumscribed in 1999. The type species '' N. nambi'' is found in Australia, South America, Central America, and Malaysia, while '' N.&nb ...

'' in 2011. * '' P. levis'' was reclassified to the genus '' Lentinus''. * '' P. sajor-caju'' was reclassified to the genus '' Lentinus''. * '' P. nidiformis'' was reclassified to the genus '' Omphalotus'' in 1994.

References

External links

* *
Pleurotus Genus
on the ''Mushroom, the Journal of Wild Mushrooming'' site

at MushroomExpert.com * {{Taxonbar, from=Q852065 Pleurotaceae Carnivorous fungi Agaricales genera Taxa named by Elias Magnus Fries Bioluminescent fungi