''Volvopluteus'' 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 ...

of small to medium-sized or big

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 ...

mushrooms A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the name "mushroom" is ...

growing worldwide. The genus has been segregated from ''

Volvariella ''Volvariella'' is a genus of fungi with deep salmon-pink gills and spore prints. Description The mushrooms lack a ring, and have an Amanita-like volva at the stem base. Some species of ''Amanita'' look similar, but ''Amanita'' has white spores ...

'' with which it shares some morphological characteristics such as the presence of a volva and a pink to pink-brown

spore print 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing warm orange ("tussock") color spore print. ...

. Phylogenetic analyses of DNA data have shown that ''Volvopluteus'' is closely related to ''

Pluteus ''Pluteus'' is a large genus of fungi with over 300 species. They are wood rotting saprobes with pink spore prints and gills that are free from the stem. The Latin word ''Pluteus'' means ''shed or penthouse''. Characteristics of the genus ...

'' and both genera currently are classified 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 ...

Pluteaceae The Pluteaceae are a family of small to medium-sized mushrooms which have free gill attachment and pink spores. Members of Pluteaceae can be mistaken for members of Entolomataceae, but can be distinguished by the angled spores and attached gills ...

, while ''Volvariella'' is not closely related to either genus and its position in the

Agaricales The Agaricales are an order (biology), order of fungi in the division (mycology), division Basidiomycota. As originally conceived, the order contained all the agarics (gilled mushrooms), but subsequent research has shown that not all agarics are ...

is still uncertain.

Etymology

''Volvopluteus'' literally means "''Pluteus'' with a volva", making reference at the same time to the close relationship between both genera and to the presence of a volva, one of the morphological characteristics that separates them.

Description

Macroscopic characters

''Volvopluteus''

fruit bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

vary from relatively small (

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...

in diameter) to large (cap in diameter), are pluteoid (i.e. with free

lamellae Lamella (: lamellae) means a small plate or flake in Latin, and in English may refer to: Biology * Lamella (mycology), a papery rib beneath a mushroom cap * Lamella (botany) * Lamella (surface anatomy), a plate-like structure in an animal * Lame ...

and discontinuous context of cap and stipe) and have a membranous white volva at the base of the stipe. The cap is ovate when young and then expands to convex or flat, it is always viscid to gelatinous when fresh and has white, grey or grey-brown color. The

gills 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 ...

are free from the stipe and they start out as white but they soon change to pink and then pinkish-brown as the spores are being produced. The stipe is centrally attached to the cap, more or less cylindrical, white and with a smooth or slightly

pruinose Pruinescence , or pruinosity, is a "frosted" or dusty-looking coating on top of a surface. It may also be called a pruina (plural: ''pruinae''), from the Latin word for hoarfrost. The adjectival form is pruinose . Entomology In insects, a "bloom" ...

surface and it has white membranous volva at the base. The odor and taste are often reported as raphanoid (radish-like) or similar to that of raw potatoes in ''V. gloiocephalus''. The spore print is pink or pinkish-brown.

Microscopic characters

Volvopluteus gloiocephalus - Basidiospores

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 ...

of ''Volvopluteus'' are relatively large (above 11

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 ...

in length), ellipsoid to oblong, relatively thick-walled and not

amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of typically 7–13 nm in diameter, a β-sheet secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human ...

dextrinoid In mycology a tissue or feature is said to be amyloid if it has a positive amyloid reaction when subjected to a crude chemical test using iodine as an ingredient of either Melzer's reagent or Lugol's solution, producing a blue to blue-black staini ...

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 usually 4-spored but 2- and 1-spored versions can sometimes occur.

Pleurocystidia A cystidium (: cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that are oft ...

and

cheilocystidia A cystidium (: cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that are oft ...

might be present or absent, and this character as well as the size and shape of these structures, can be used for morphologically separating the different species of the genus. The

pileipellis The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body. It covers the trama, the fleshy tissue of the fruit body. The pileipellis is more or less synonymous with the cuticle, but the cuticle generally describes ...

is an ixocutis composed of parallel

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 o ...

e embedded in a gelatinous matrix. The stipitipellis is a cutis and can be set with cylindrical

caulocystidia A cystidium (: cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that are oft ...

Clamp connections A clamp connection is a hook-like structure formed by growing hyphal cells of certain fungi. It is a characteristic feature of basidiomycete fungi. It is created to ensure that each cell, or segment of hypha separated by septa (cross walls), recei ...

are absent from hyphae in all parts of the fruit body.

Ecology

All species of ''Volvopluteus'' are

saprotrophs 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 ...

, and grow terrestrially in gardens, grassy fields (in or outside forests) and on accumulations of vegetable matter (compost, wood chips).

Classification

The type species, ''Volvopluteus gloiocephalus'', has been traditionally included in the genus ''Volvariella''. The first comprehensive

molecular phylogeny Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

of the Agaricales by Moncalvo et al. sampled two species of ''Volvariella'' ('' V. volvacea'' and '' V. hypophytis'') that were placed in a distant position from ''Pluteus''. The study of Matheny et al. in 2006 included ''Volvariella gloiocephala'' that was placed as the sister group of ''Pluteus''. The 2011 study of Justo et al. included a broader sampling of ''Volvariella'' species and confirmed that the genus, as traditionally defined, was

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

: (i) the bulk of the genus, including the paddy-straw mushroom ''Volvariella volvacea'', is not closely related to ''Pluteus'' and (ii) the group of species around ''Volvariella gloiocephala'' forms a separate lineage that constitutes the

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of ''Pluteus''. The name ''Volvopluteus'' was then proposed to accommodate the latter group. ''Volvopluteus'' differs from ''Volvariella'' morphologically by the average spore length over 11 μm and the

composed of relatively thin

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 ...

embedded in a conspicuous gelatinous matrix. The same characters and the presence of a volva separate ''Volvopluteus'' from ''Pluteus''. All three genera are characterized by the pink to pink-brown spore prints and inverse hymenophoral trama.

Distribution

The genus is

cosmopolitan Cosmopolitan may refer to: Internationalism * World citizen, one who eschews traditional geopolitical divisions derived from national citizenship * Cosmopolitanism, the idea that all of humanity belongs to a single moral community * Cosmopolitan ...

and has been reported from all

continents A continent is any of several large geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single large landmass, a part of a very large landmass, as in the case of As ...

except

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

Edibility

''Volvopluteus gloiocephalus'' is

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from " eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushroo ...

although is cited as mediocre or of poor quality. Young specimens of ''V. gloiocephalus'' have white gills so it is possible to mistake them for an ''

Amanita The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded Edible mushroom, edible species (and many species of unknown edibility). The genus is re ...

'' and vice versa. The edibility of other species of the genus is not known.

Species

Four species are currently accepted in the genus: *'' Volvopluteus asiaticus'' Justo & Minnis *'' Volvopluteus earlei'' (Murrill) Vizzini, Contu & Justo *''

Volvopluteus gloiocephalus ''Volvopluteus gloiocephalus'', commonly known as the big sheath mushroom, rose-gilled grisette, or stubble rosegill, is a species of mushroom in the family Pluteaceae. For most of the 20th century it has been known under the names ''Volvarie ...

'' (DC) Vizzini, Contu & Justo *'' Volvopluteus michiganensis'' (A.H. Sm.) Justo & Minnis Other species that probably belong in ''Volvopluteus'' based on their morphological characteristics: *'' Volvaria microchlamida'' (Speg.) Sacc. Originally described from

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

. *''

Volvariella alabamensis ''Volvariella'' is a genus of fungi with deep salmon-pink gills and spore prints. Description The mushrooms lack a ring, and have an Amanita-like volva at the stem base. Some species of ''Amanita'' look similar, but ''Amanita'' has white spores ...

'' (Murrill) Shaffer. Originally described from

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

(USA). *'' Volvariella arenaria'' (Pat.) Singer. Originally described from the

Arabian Desert The Arabian Desert () is a vast desert wilderness in West Asia that occupies almost the entire Arabian Peninsula with an area of . It stretches from Yemen to the Persian Gulf and Oman to Jordan and Iraq. It is the fourth largest desert in the ...

. *'' Volvariella californica'' (Earle) Singer. Originally described from

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

(USA). *'' Volvariella canalipes'' (Murrill) Shaffer. Originally described from

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

(USA). *'' Volvariella cnemidophora'' (Mont.) Singer. Originally described from

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. *''

Volvariella insignis ''Volvariella'' is a genus of fungi with deep salmon-pink gills and spore prints. Description The mushrooms lack a ring, and have an Amanita-like volva at the stem base. Some species of ''Amanita'' look similar, but ''Amanita'' has white spores ...

'' Heinem. Originally described from the

Democratic Republic of Congo The Democratic Republic of the Congo (DRC), also known as the DR Congo, Congo-Kinshasa, or simply the Congo (the last ambiguously also referring to the neighbouring Republic of the Congo), is a country in Central Africa. By land area, it is t ...

*''

Volvariella macrospora ''Volvariella'' is a genus of fungi with deep salmon-pink gills and spore prints. Description The mushrooms lack a ring, and have an Amanita-like volva at the stem base. Some species of ''Amanita'' look similar, but ''Amanita'' has white spores ...

'' Singer. Originally described from

. *'' Volvariella stercoraria'' (Peck) Singer. Originally described from

Kansas Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named a ...

(USA). All these species are only known from their respective original descriptions, making it very difficult to establish if they represent independent

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

. For this reason they have not been formally reclassified in the genus ''Volvopluteus''.

References

{{taxonbar , from=Q7941350 Pluteaceae Agaricales genera