''Pholiotina'' is a genus of small agaric fungi. It was circumscribed by Swiss mycologist

Victor Fayod Victor Fayod (23 November 1860 – 28 April 1900) was a Swiss mycologist, who created an influential novel classification of the agaric fungi and who described a number of new genera and species. Biographical overview Fayod was born on 23 Nove ...

in 1889 for '' Conocybe''-like species with partial veils. The genus has since been expanded to include species lacking partial veils.

Taxonomic details

The genus ''Pholiotina'' is defined as small thin '' Mycena''-like mushrooms, 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 surface, cystidia 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. Victor Fayod designated ''Pholiotina blattaria'' as the type species 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 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 '' Conocybe''. However, a molecular phylogenetics study has shown that, while ''Pholiotina'' as currently defined is polyphyletic, the three clades 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 cystidia 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 ''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 polyphyletic, 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 ''Descolea'' is a genus of fungi in the family Bolbitiaceae. Described by mycologist Rolf Singer in 1952, the widespread genus contains about 15 species. It was formerly placed in the family Cortinariaceae because of its limoniform basidiospores ...

'', another forming the sister group to '' Bolbitius'' 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 guides 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 polyphyletic, some of these species will likely be moved to other genera.

References

{{Taxonbar, from=Q4491390 Bolbitiaceae Agaricales genera