Mycena nargan
Encyclopedia
Mycena nargan, commonly known as the Nargan's bonnet, is a species of fungus
in the Mycenaceae
family, and the sole member of the section Nargan in the genus Mycena
. Reported as a new species in 1995, it is known predominantly from Southern Australia. The saprobic fungus produces mushroom
s that grow on well-decayed wood, often on the underside of wood lying in litter. The dark chestnut
-coloured caps
are covered with white, easily removed scales, and reach diameters of up to 2 cm (0.78740157480315 in) wide. The pale, slender stems
are up to 5 cm (2 in) long and have white scales at the base. On the underside of the cap, the cream-coloured gills are widely spaced and bluntly attached
to the stem. The edibility
of the mushroom is unknown.
, South Australia, and reported as new to science in a 1995 Australian Systematic Botany
publication. The species name refers to the nargan or nargun
, a mythical aboriginal
being – originally the mycologists Tom May
and Bruce Fuhrer
had called it "nargan", as its white speckles glistened in the dark like the eyes of the nargan, and Cheryl Grgurinovic incorporated this into its specific epithet. It is commonly
known as "Nargan's bonnet", but has also been referred to as the "spotted pixie cap".
With respect to infrageneric classification (i.e., taxonomic
ranking below the level of genus
) in Mycena
, several characteristics suggest the mushroom fits best in Rudolph Arnold Maas Geesteranus
' section Fragilipedes: the ellipsoidal, amyloid
spores; dextrinoid spore-bearing tissue
; smooth cheilocystidia; gills with the edge the same colour as the face; and the non-slimy, distinctly coloured cap. According to the 1986 infrageneric classification proposed by Rolf Singer
, the mushroom would be classified in subgenus
Mycena, subsection Ciliatae, stirps Alcalina (roughly equivalent to section Fragilipedes of Maas Geesteranus) because of the amyloid spores, smooth, elongated cheilocystidia, dull-coloured pigment, and stem without either latex
or a slimy sheath. Grgurinovic erected the new section Nargan to accommodate M. nargan, because its scales, lack of coarse fibrils at the base of the stem, and lack of pruinose coating meant it was not a good fit for section Fragilipedes.
s of young mushrooms are initially egg-shaped to conical, expanding to become bell-shaped and up to 2 cm (0.8 in) in diameter. Initially, the margin of the cap is rolled inwards; it typically assumes a lighter colour than the centre of the cap surface. Dark brown in colour, the mushroom is distinguished by the presence of white speckles or scales on the cap and stem
; these scales may disappear when they become sloughed off or washed away by rain, which can make the species hard to recognise. The thick gills have an adnate
attachment to the stem (broadly attached to the stem slightly above the bottom of the gill, with most of the gill fused to the stem), and are white to light grey in colour, paler toward the edge. There are about 24–28 gills extending completely from the cap margin to the stem, and one or two tiers of lamellulae (shorter gills does do not extend fully from the margin to the stem). The thin stem is up to 4 cm (1.6 in) high and 0.3 cm (0.12 in) wide, and does not have a ring
. Young specimens will typically have whitish scales at the base; later, these will slough off and a felt-like whitish mycelium
may be apparent. The mushroom have no distinctive odour. The spore print
is white or cream. The edibility
of the mushroom has not been reported.
s of M. nargan are roughly ellipsoid, smooth, hyaline
, and measure 7.4–10.4 by 4.8–7.1 μm
. They have a small, oblique apiculus, and lack oil droplets. In terms of staining reactions, they are acyanophilous (not absorbing methyl blue
dye), and amyloid
(turning blue-black in Melzer's reagent
). The basidia (spore-bearing cells in the hymenium
) are club-shaped, have clamp connection
s at their bases, and measure 29.6–36.4 by 8.2–10.7 μm. They are four-spored, and the spores are attached to the basidia by long slender sterigmata that are up to 7.2 μm long. The gill edge is sterile (without basidia), and has adundant cystidia. These thin-walled cheilocystidia range in shape from swollen in the middle with a beak-like point, to spindle-shaped (fusiform) to club-shaped. They are smooth, hyaline, and inamyloid, with dimensions of 20.8–38.4 by 4.8–10.4 μm. They have a clamp connection at base. Pleurocystidia (cystidia on the gill face) are not present in this species. The gill tissue is made of smooth, thin-walled cylindrical to egg-shaped cells, up to 30.4 μm in diameter. The cells are dextrinoid (producing a black to blue-black positive reaction with Melzer's reagent), and reddish-brown. The surface of the cap (the pileipellis
) is made of a layer of bent-over filamentous hyphae measuring 1.8–4.8 μm. These loosely arranged hyphae are slightly gelatinised, smooth, thin-walled, hyaline, inamyloid, and have clamp connections. The tissue layer directly under the pileipellis (the hypodermium) has cells containing brown pigment
. The cap tissue consists of smooth, thin-walled, cylindrical to broadly cylindrical or ovoid cells, up to 37.0 μm in diameter, with clamp connections. These cells are dextrinoid and reddish orange-brown in colour. The surface of the stem is made of filamentous hyphae, 2.2–4.0 μm in diameter, either smooth or with sparse to moderately dense short, rod-like to cylindrical projections. The cells are thin-walled to very slightly thick-walled, hyaline, inamyloid, and have clamp connections. Caulocystidia (cystidia on the cap surface) are not present. The stem tissue consists of short, cylindrical cells, up to 28.0 μm in diameter that are smooth, thin-walled, and with or without brown pigment in the cytoplasm
. The cells contain clamp connections and are reddish orange-brown.
's 2005 book A Field Guide to Australian Fungi was labelled as Mycena nivalis, a species with a white cap.
and Pinus pinaster. Fruit bodies usually appear from April to June. The species has been recorded from Tasmania
, Victoria
and southeastern South Australia
. The Australian Fungimap initiative has reported isolated collections in Western Australia
, South Australia, and New South Wales
, although the majority of sightings have been in Tasmania and Victoria. The fungus is saprobic, meaning it derives nutrients from dead or dying organic matter. A field study conducted in Tasmania showed that it is much more likely to be found in mature eucalypt
forest (defined as having grown at least 70 years before the last wildfire
) than young, regenerating forest that had experienced clearfelling, burning, and sowing two to three years previously.
Fungus
A fungus is a member of a large 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, Fungi, which is separate from plants, animals, and bacteria...
in the Mycenaceae
Mycenaceae
The Mycenaceae are a family of fungi in the order Agaricales. According to the Dictionary of the Fungi , the family contains 10 genera and 705 species. This is one of several families that were separated from the Tricholomataceae as a result of phylogenetic analyses...
family, and the sole member of the section Nargan in the genus Mycena
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 brown, but a few species have brighter colors. Most have a...
. Reported as a new species in 1995, it is known predominantly from Southern Australia. The saprobic fungus produces mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s that grow on well-decayed wood, often on the underside of wood lying in litter. The dark chestnut
Chestnut (color)
Chestnut, also known as Indian red, is a color, a medium brownish shade of red, and is named after the nut of the chestnut tree.As Indian red, it is named after the red laterite soil found in India. It is thus an earth tone as well as a red. It is composed of naturally occurring iron oxides. Other...
-coloured caps
Pileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
are covered with white, easily removed scales, and reach diameters of up to 2 cm (0.78740157480315 in) wide. The pale, slender stems
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
are up to 5 cm (2 in) long and have white scales at the base. On the underside of the cap, the cream-coloured gills are widely spaced and bluntly attached
Adnation
Adnation in plants is the "union of unlike parts; organically united or fused with another dissimilar part, e.g. an ovary to a calyx tube, or stamens to petals". This is in contrast to connation, the fusion of similar organs....
to the stem. The edibility
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
of the mushroom is unknown.
Taxonomy, naming, and classification
The species was first discovered in 1992 in Kuitpo ForestKuitpo Forest
Kuitpo Forest is situated about 40 km south-east of Adelaide central business district in Australia.Established in 1898, Kuipto Forest was the first of many forest plantations in the Mount Lofty Ranges, planted at the turn of the 20th century to ensure a sustainable timber supply for South...
, South Australia, and reported as new to science in a 1995 Australian Systematic Botany
Australian Systematic Botany
Australian Systematic Botany is a peer-reviewed international journal that publishes original research, and sometimes review articles, on topics related to systematic botany, such as biogeography, taxonomy and evolution. It is published by CSIRO Publishing...
publication. The species name refers to the nargan or nargun
Nargun
According to Gunai/Kurnai tribal legends, the Nargun is a fierce half-human half-stone female creature that lived in the Den of Nargun, a cave under a rock overhang behind a small waterfall in the Mitchell River National Park, Victoria, Australia. Aboriginal legend describes the Nargun as a beast...
, a mythical aboriginal
Australian Aborigines
Australian Aborigines , also called Aboriginal Australians, from the latin ab originem , are people who are indigenous to most of the Australian continentthat is, to mainland Australia and the island of Tasmania...
being – originally the mycologists Tom May
Tom May (mycologist)
Thomas William May is a mycologist and the curator of the fungal collection at the National Herbarium of Victoria where he specialises in the taxonomy and ecology of Australian macrofungi. He is most notable for the comprehensive bibliographical lists of all Australian fungi published thus far;...
and Bruce Fuhrer
Bruce A. Fuhrer
Bruce Alexander Fuhrer is an Australian mycologist. He was awarded the Australian Natural History Medallion in 1989 and is a Life Member of the Ringwood Field Naturalists Club. He has written many books on Australian fungi, including a Comprehensive Field Guide to Australian Fungi. He worked for 25...
had called it "nargan", as its white speckles glistened in the dark like the eyes of the nargan, and Cheryl Grgurinovic incorporated this into its specific epithet. It is commonly
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
known as "Nargan's bonnet", but has also been referred to as the "spotted pixie cap".
With respect to infrageneric classification (i.e., taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
ranking below the level of genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
) in Mycena
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 brown, but a few species have brighter colors. Most have a...
, several characteristics suggest the mushroom fits best in Rudolph Arnold Maas Geesteranus
Rudolph Arnold Maas Geesteranus
Rudolph Arnold Maas Geesteranus, born 20 January 1911 in The Hague, died May 18 2003 in Oegstgeest, was a Dutch mycologist.-References:...
' section Fragilipedes: the ellipsoidal, amyloid
Amyloid (mycology)
In mycology the term amyloid refers to a crude chemical test using iodine in either Melzer's reagent or Lugol's solution, to produce a black to blue-black positive reaction. It is called amyloid because starch gives a similar reaction, and that reaction for starch is also called an amyloid reaction...
spores; dextrinoid spore-bearing tissue
Hymenophore
A hymenophore refers to the hymenium-bearing structure of a fungal fruiting body. Hymenophores can be smooth surfaces, lamellae, folds, tubes, or teeth....
; smooth cheilocystidia; gills with the edge the same colour as the face; and the non-slimy, distinctly coloured cap. According to the 1986 infrageneric classification proposed by Rolf Singer
Rolf Singer
Rolf Singer was a German-born mycologist and one of the most important taxonomists of gilled mushrooms in the 20th century....
, the mushroom would be classified in subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
Mycena, subsection Ciliatae, stirps Alcalina (roughly equivalent to section Fragilipedes of Maas Geesteranus) because of the amyloid spores, smooth, elongated cheilocystidia, dull-coloured pigment, and stem without either latex
Latex
Latex is the stable dispersion of polymer microparticles in an aqueous medium. Latexes may be natural or synthetic.Latex as found in nature is a milky fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins,...
or a slimy sheath. Grgurinovic erected the new section Nargan to accommodate M. nargan, because its scales, lack of coarse fibrils at the base of the stem, and lack of pruinose coating meant it was not a good fit for section Fragilipedes.
Description
The capPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
s of young mushrooms are initially egg-shaped to conical, expanding to become bell-shaped and up to 2 cm (0.8 in) in diameter. Initially, the margin of the cap is rolled inwards; it typically assumes a lighter colour than the centre of the cap surface. Dark brown in colour, the mushroom is distinguished by the presence of white speckles or scales on the cap and stem
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
; these scales may disappear when they become sloughed off or washed away by rain, which can make the species hard to recognise. The thick gills have an adnate
Adnation
Adnation in plants is the "union of unlike parts; organically united or fused with another dissimilar part, e.g. an ovary to a calyx tube, or stamens to petals". This is in contrast to connation, the fusion of similar organs....
attachment to the stem (broadly attached to the stem slightly above the bottom of the gill, with most of the gill fused to the stem), and are white to light grey in colour, paler toward the edge. There are about 24–28 gills extending completely from the cap margin to the stem, and one or two tiers of lamellulae (shorter gills does do not extend fully from the margin to the stem). The thin stem is up to 4 cm (1.6 in) high and 0.3 cm (0.12 in) wide, and does not have a ring
Annulus (mycology)
An annulus is the ring like structure sometimes found on the stipe of some species of mushrooms. The annulus represents the remaining part of the partial veil, after it has ruptured to expose the gills or other spore-producing surface. An annulus may be thick and membranous, or it may be cobweb-like...
. Young specimens will typically have whitish scales at the base; later, these will slough off and a felt-like whitish mycelium
Mycelium
thumb|right|Fungal myceliaMycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae. The mass of hyphae is sometimes called shiro, especially within the fairy ring fungi. Fungal colonies composed of mycelia are found in soil and on or within many other...
may be apparent. The mushroom have no distinctive odour. The spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
is white or cream. The edibility
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
of the mushroom has not been reported.
Microscopic characteristics
The sporeSpore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s of M. nargan are roughly ellipsoid, smooth, hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
, and measure 7.4–10.4 by 4.8–7.1 μm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
. They have a small, oblique apiculus, and lack oil droplets. In terms of staining reactions, they are acyanophilous (not absorbing methyl blue
Methyl blue
Methyl blue, also known as Cotton blue, Helvetia blue, Acid blue 93, or C.I. 42780, is a chemical compound with the molecular formula C37H27N3Na2O9S3. It is used as a stain in histology. Methyl blue stains collagen blue in tissue sections. It is soluble in water and slightly soluble in ethanol...
dye), and amyloid
Amyloid (mycology)
In mycology the term amyloid refers to a crude chemical test using iodine in either Melzer's reagent or Lugol's solution, to produce a black to blue-black positive reaction. It is called amyloid because starch gives a similar reaction, and that reaction for starch is also called an amyloid reaction...
(turning blue-black in Melzer's reagent
Melzer's Reagent
Melzer's reagent is a chemical reagent used by mycologists to assist with the identification of fungi.-Composition:...
). The basidia (spore-bearing cells in the hymenium
Hymenium
The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some cells develop into sterile cells called cystidia or...
) are club-shaped, have clamp connection
Clamp connection
A clamp connection is a structure formed by growing hyphal cells of certain fungi. It is created to ensure each septum, or segment of hypha separated by crossed walls, receives a set of differing nuclei, which are obtained through mating of hyphae of differing sexual types...
s at their bases, and measure 29.6–36.4 by 8.2–10.7 μm. They are four-spored, and the spores are attached to the basidia by long slender sterigmata that are up to 7.2 μm long. The gill edge is sterile (without basidia), and has adundant cystidia. These thin-walled cheilocystidia range in shape from swollen in the middle with a beak-like point, to spindle-shaped (fusiform) to club-shaped. They are smooth, hyaline, and inamyloid, with dimensions of 20.8–38.4 by 4.8–10.4 μm. They have a clamp connection at base. Pleurocystidia (cystidia on the gill face) are not present in this species. The gill tissue is made of smooth, thin-walled cylindrical to egg-shaped cells, up to 30.4 μm in diameter. The cells are dextrinoid (producing a black to blue-black positive reaction with Melzer's reagent), and reddish-brown. The surface of the cap (the pileipellis
Pileipellis
thumb|300px||right|The cuticle of some mushrooms, such as [[Russula mustelina]] shown here, can be peeled from the cap, and may be useful as an identification feature....
) is made of a layer of bent-over filamentous hyphae measuring 1.8–4.8 μm. These loosely arranged hyphae are slightly gelatinised, smooth, thin-walled, hyaline, inamyloid, and have clamp connections. The tissue layer directly under the pileipellis (the hypodermium) has cells containing brown pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
. The cap tissue consists of smooth, thin-walled, cylindrical to broadly cylindrical or ovoid cells, up to 37.0 μm in diameter, with clamp connections. These cells are dextrinoid and reddish orange-brown in colour. The surface of the stem is made of filamentous hyphae, 2.2–4.0 μm in diameter, either smooth or with sparse to moderately dense short, rod-like to cylindrical projections. The cells are thin-walled to very slightly thick-walled, hyaline, inamyloid, and have clamp connections. Caulocystidia (cystidia on the cap surface) are not present. The stem tissue consists of short, cylindrical cells, up to 28.0 μm in diameter that are smooth, thin-walled, and with or without brown pigment in the cytoplasm
Cytoplasm
The cytoplasm is a small gel-like substance residing between the cell membrane holding all the cell's internal sub-structures , except for the nucleus. All the contents of the cells of prokaryote organisms are contained within the cytoplasm...
. The cells contain clamp connections and are reddish orange-brown.
Similar species
Mycena nargan has a very distinct appearance, and is unlikely to be mistaken for other Mycenas. However, one noted unintentional misidentification occurred when the M. nargan on the cover photograph of Bruce A. FuhrerBruce A. Fuhrer
Bruce Alexander Fuhrer is an Australian mycologist. He was awarded the Australian Natural History Medallion in 1989 and is a Life Member of the Ringwood Field Naturalists Club. He has written many books on Australian fungi, including a Comprehensive Field Guide to Australian Fungi. He worked for 25...
's 2005 book A Field Guide to Australian Fungi was labelled as Mycena nivalis, a species with a white cap.
Habitat and distribution
A common mushroom, Mycena nargan is found growing singly or in clusters on the underside of rotting wood in wet and shaded areas, and is especially partial to EucalyptusEucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
and Pinus pinaster. Fruit bodies usually appear from April to June. The species has been recorded from Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
, Victoria
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
and southeastern South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
. The Australian Fungimap initiative has reported isolated collections in Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
, South Australia, and New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
, although the majority of sightings have been in Tasmania and Victoria. The fungus is saprobic, meaning it derives nutrients from dead or dying organic matter. A field study conducted in Tasmania showed that it is much more likely to be found in mature eucalypt
Eucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
forest (defined as having grown at least 70 years before the last wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
) than young, regenerating forest that had experienced clearfelling, burning, and sowing two to three years previously.