''Pholiotina'' 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 ...

of small

agaric An agaric () is a type of fungus fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. In the UK, agarics are called "mushrooms ...

fungi. It was circumscribed by Swiss mycologist Victor Fayod in 1889 for ''

Conocybe ''Conocybe'' is a genus of mushrooms with ''Conocybe tenera'' as the type species and at least 243 other species. There are at least 50 different species in North America. Most have a long, thin fragile stipe and are delicate, growing in grassl ...

''-like species with

partial veil In mycology, a partial veil (also called an inner veil, to differentiate it from the "outer", or universal veil) is a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics. Its role is to isola ...

s. The genus has since been expanded to include species lacking partial veils.

Taxonomic details

The genus ''Pholiotina'' is defined as small thin ''

Mycena ''Mycena'' is a large genus of small saprotrophic mushrooms that are rarely more than a few centimeters in width. They are characterized by a white spore print, a small conical or bell-shaped cap, and a thin fragile stem. Most are gray or br ...

''-like

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, with an hymenoderm

pileipellis The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowe ...

, a dry

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. Caps typically have a visor, or no brim at all. They are popular in casual and informal se ...

surface,

cystidia A cystidium (plural 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 ar ...

that are sub-capitate to blunt, and spores which are rusty brown in deposit.

Spore 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 ...

s of mushrooms of this genus are thick walled, smooth and have a

germ pore A germ pore is a small pore in the outer wall of a fungal spore through which the germ tube exits upon germination. It can be apical or eccentric in its location, and, on light microscopy, may be visualized as a lighter coloured area on the cell ...

. Victor Fayod designated ''Pholiotina blattaria'' as the

type species In 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 species that contains the biological type specimen ...

of ''Pholiotina'', but this name was used for many different species of ''Pholiotina'' with partial veils and it is unclear which species is really ''P. blattaria'', which makes it a

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...

. He designated a

lectotype In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes the ...

for this species in the same publication, and microscopic examination revealed that this specimen belongs to the species ''P. vexans'', making ''P. vexans'' the current type species of ''Pholiotina''. Some authors considered ''Pholiotina'' part of the genus ''

''. However, a

molecular phylogenetics 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 ...

study has shown that, while ''Pholiotina'' as currently defined is

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

, the three

clades 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, t ...

that have been placed in ''Pholiotina'' are more closely related to other genera than to ''Conocybe''. The two genera can be distinguished microscopically: ''Pholiotina'' contains a differentiated central zone called a mediostratum that is lacking in ''Conocybe''. Additionally, most ''Pholiotina'' species have

with rounded to tapered tips, compared to the enlarged, globular cystidial tips of ''Conocybe''. In a 2007 publication, Hausknecht and Krisai-Greilhuber devised an infrageneric

classification Classification is a process related to categorization, the process in which ideas and objects are recognized, differentiated and understood. Classification is the grouping of related facts into classes. It may also refer to: Business, organizat ...

that includes the

sections Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sig ...

''Piliferae'' and ''Vestitae'', and the

series Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used in ...

''Aeruginosa'', ''Aporos'', ''Appendiculata'', ''Brunnea'', ''Coprophila'', ''Filipes'', ''Keniensis'', ''Mairei'', ''Pygmaeoaffinis'', ''Resinosocystidiata'', ''Sulcata'', ''Teneroides'', ''Utriformis'', and ''Vexans''. However, a 2013 study by Tóth '' et al.'' found ''Pholiotina'' as it is currently defined to be

, with one

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, ...

forming 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 t ...

to '' Descolea'', another forming the sister group to ''

Bolbitius ''Bolbitius'' is a genus of small mushrooms in the family Bolbitiaceae. Description The genus ''Bolbitius'' is defined as small thin ''Mycena''-like mushrooms, with a hymenoderm pileipellis, a glutinous cap surface, and spores that are brown i ...

'' and another forming the sister group to ''

Galerella nigeriensis ''Herpestes'' is a genus within the mongoose family Herpestidae. Several species in the family are known as slender mongooses. It is the type genus of the family, and comprises 5-6 living species, each with several subspecies. Fossil remains of ...

''. All the species of ''Pholiotina'' with partial veils and some species without, including the type species, ''P. vexans'', formed a

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 ...

clade closely related to ''Descolea''. It is likely that the species in this clade will be kept as ''Pholiotina'' species, while the species in the other two clades will be removed to other genera, but this has not happened yet. This study also found some of the sections named by Hausknecht and Krisai-Greilhuber to be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

or polyphyletic.

Notable species

Pholiotina rugosa ''Pholiotina rugosa'' is a common mushroom which is widely distributed and especially common in the Pacific Northwest. It grows in woodchips, flowerbeds and compost. It has been found in Europe, Asia and North America. It contains the same mycot ...

'' is the most commonly known species of this genus, although in most

field guide A field guide is a book designed to help the reader identify wildlife (flora or fauna) or other objects of natural occurrence (e.g. rocks and minerals). It is generally designed to be brought into the "field" or local area where such objects exi ...

s this species is known as ''Conocybe filaris'', which is a

junior synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...

. It is a deadly poisonous species. ''Pholiotina'' also includes the

psychoactive A psychoactive drug, psychopharmaceutical, psychoactive agent or psychotropic drug is a chemical substance, that changes functions of the nervous system, and results in alterations in perception, mood, consciousness, cognition or behavior. Th ...

species '' P. cyanopus'' and '' P. smithii''. Since ''Pholiotina'' under the current definition is

, some of these species will likely be moved to other genera.

References

{{Taxonbar, from=Q4491390 Bolbitiaceae Agaricales genera