''Polytolypa'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

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 ...

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 ...

containing the single species ''Polytolypa hystricis''. First classified in the

Onygenaceae The Onygenaceae are a family (biology), family of fungi in the Ascomycota, class Eurotiomycetes. Genera These are the genera that are in the Onygenaceae, according to a 2021 review of fungal classification. Following the genus name is the Author ...

family, as of 2008 it is considered to be in the

Ajellomycetaceae The Ajellomycetaceae are a family of fungi in the Ascomycota, class Eurotiomycetes. The family contains eight genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as vi ...

, although there is still uncertainty as to its

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

relationships with other similar genera. This species is only known from a single specimen derived in the laboratory from a specimen of dung of the North American porcupine, ''Erethizon dorsatum'', collected in Ontario, Canada. ''Polytolypa hystricis'' contains bioactive compounds that have

antifungal An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as crypto ...

activity.

Taxonomy, phylogeny, and naming

160px, left, ''Polytolypa hystricis'' was initially grown from the dung of the North American porcupine, ''Erethizon dorsatum'' (pictured).The genus was first described in 1993 by

University of Toronto The University of Toronto (UToronto or U of T) is a public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution ...

mycologists J.A. Scott and D.W. Malloch, who grew the fungus in moist chamber cultures of porcupine dung collected in Stoneleigh,

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

, Canada. The

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name ''Polytolypa'' is from the Greek word ''poly'' (πολυ) meaning "many", and ''tolype'' (τολυπη), meaning "skein of yarn". The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''hystricis'' comes from the Greek ''hystrix'' (υστριξ), or "porcupine". The genus has been classified in the

, a fungal

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

characterized by species capable of digesting human hair ''in vitro'', and with spores that are

punctate Punctum, plural puncta, adjective punctate, is an anatomical term for a sharp point or tip. It may also refer to: Medical *Lacrimal punctum, a minute opening on the margins of the eyelids that collect tears produced by the lacrimal glands *Blin ...

(with minute surface punctures) when viewed with scanning electron microscopy. However, as Scott and colleagues demonstrated using traditional laboratory tests to determine keratinolytic activity, ''P. hystricus'' is not able to digest hair. There is still uncertainty as to its

relationships with other similar genera. ''Polytolypa'' is thought to be evolutionarily most closely related to the genera '' Malbranchea'' and ''

Spiromastix ''Spiromastix'' is a genus of fungi within the Onygenaceae family. References External links *Spiromastix' at Index Fungorum ''Index Fungorum'' is an international project to index all formal names ( scientific names) in the fungus kingdom. ...

''. The grouping of ''Polytolypa'' and ''Spiromastix'' represent a

sister clade 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 the Ajellomyces clade, based on analysis of partial nuclear LSU sequence data. However, the

s of ''Polytolypa'' are still unclear and await further study. The 10th edition of the ''Dictionary of the Fungi'' (2008) considers the genus to be in the

family, although uncertainty with this classification is indicated in the entry; in contrast, the online mycological database MycoBank classifies the genus in the Onygenaceae.

Description

The ascus-containing reproductive structures, or '' ascomata'', are minute, spherical bodies, typically 200–400

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

in diameter. They start out white, but gradually become rusty brown in maturity. The ascomata, which may be clustered together in groups or scattered about, grow in a shallow layer of "hairs" (actually fungal

mycelia Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates in ...

) called a

tomentum Tomentum may refer to: * Plant trichomes, a covering of closely matted or fine hairs on plant leaves. * Tomentum (anatomy) Tomentum may refer to: * Plant trichomes, a covering of closely matted or fine hairs on plant leaves. * Tomentum (ana ...

. The ascomata have "appendages" composed of numerous coiled, sometimes branched helices of

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 that are coiled 3–15 times. The

ascospore An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or s ...

s produced by ''Polytolypa'' are ellipsoidal, yellow to yellow-orange in color, with dimensions of 2.5–5 by 3–4 μm. Viewed with a

light microscope The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects. Optical microscopes are the oldest design of microsco ...

their surfaces appear to be smooth, but under scanning electron microscopy, they are revealed to be densely marked with punctures and small, hard, sharp projections. The structures that produce the ascospores are called

asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

. In ''Polytolypa'' they are numerous, spherical, and measure 9–10 by 12–13 μm. Each ascus contains eight ascospores, which are released when the ascus dissolves away at maturity. The

anamorph In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota: *Teleomorph: the sexual reproductive stage (morph), typically a fruiting body. *Anamorph: an ase ...

(asexual form of the fungus) resembles the genus ''

Chrysosporium ''Chrysosporium'' is a genus of hyaline hyphomycetes fungi in the family Onygenaceae. ''Chrysosporium'' colonies are moderately fast-growing, flat, white to tan to beige in color; they often have a powdery or granular surface texture. Hyaline, ...

''.

Habitat and distribution

''Polytolypa hystricis'' is known only from the dung of the North American porcupine, ''Erethizon dorsatum''. Porcupine dens accumulate thick layers of nutrient-rich dung, hair and urine that are degraded by a

succession Succession is the act or process of following in order or sequence. Governance and politics *Order of succession, in politics, the ascension to power by one ruler, official, or monarch after the death, resignation, or removal from office of ...

of fungi. These fungi are disseminated by

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s (such as insects) or by the porcupine themselves.

Bioactive compounds

Chemical analysis Analytical chemistry studies and uses instruments and methods to separate, identify, and quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separati ...

has shown that ''Polytolypa hystricis'' contains a unique

triterpenoid Triterpenes are a class of chemical compounds composed of three terpene units with the molecular formula C30H48; they may also be thought of as consisting of six isoprene units. Animals, plants and fungi all produce triterpenes, including squale ...

chemical named polytolypin, as well two compounds known previously as

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

s from Scleroderris Canker (''

Gremmeniella abietina Scleroderris canker (American name), or Brunchorstia disease (European name), ''Gremmeniella abietina'', is a species of fungal diseases infecting coniferous forests. The main symptom is the death of the needles, leading to the death of the tree ...

''). Both polytolypin and one of the previously identified compounds have "moderate"

activity against the species '' Ascobolus furfuraceous'', while polytopin alone can inhibit the growth of '' Candida albicans''.

References

External links