Mycena flavoalba
Encyclopedia
Mycena flavoalba, commonly known as the ivory bonnet, is a species of inedible mushroom
in the Mycenaceae
family. The cap
is initially conical in shape, before becoming convex and then flattening out; it may reach dimensions of up to 1.5 cm (0.590551181102362 in) across. The cap color is ivory-white to yellowish white, sometimes more yellowish at the center. The tubular stems
are up to 8 cm (3.1 in) long and 2.5 mm (0.0984251968503937 in) thick, and have long, coarse white hairs at their bases. The mushroom is found in Europe, the Middle East, and North America, where it grows scattered or in dense groups under conifers and on humus in oak
woods.
in 1838, it was assigned its current name in 1872 by Lucien Quélet
. American mycologist Rolf Singer
transferred the species to the genera Hemimycena
and Marasmiellus
in 1938 and 1951, respectively. Singer later changed his mind about these placements, and his 1986 Agaricales in Modern Taxonomy, he considered the species a Mycena. The binomials resulting from these transfers are considered synonyms
; another synonym is Mycena luteoalba (Bolton) Gray.
Mycena flavoalba is placed in the section Adonideae of the genus Mycena
, alongside species such as and .
The specific epithet flavoalba ("yellow-white") is a compound of the Latin
adjectives flavus ("yellow) and alba ("white"). The mushroom's common name
is the "ivory bonnet".
of M. flavoalba is 1 – in diameter, conical when young, becoming somewhat bell-shaped, broadly conic or at times nearly convex. It may develop a papilla (a nipple-like structure) in its center. The cap margin is initially pressed against the stem, but in maturity either flares out or curves inward slightly. The cap surface is smooth, moist, and partially translucent, so that the outline of the gills underneath the cap may be seen. The mushroom is hygrophanous
(changing color as it loses or gains moisture), being cream-buff to yellowish initially, with a paler (almost white) margin, and fading to buff in the center and yellowish-white along the margin when dry. The flesh
is yellowish to white, thick under the disc but otherwise thin, moderately fragile, and without any distinctive odor and taste.
The gills are ascending and somewhat hooked or toothed, narrow at first but becoming rather broad (2.5 mm and becoming 3–4 mm). They are nearly equal in width throughout or slightly ventricose
in age, with a spacing that is close to subdistant. About 18–24 gills reach the stem, with two tiers of lamellulae (short gills that do not extend fully from the cap margin to the stem) that may develop veins running between them. The gills are white to creamy-white with edges that are even and whitish, and waxy in appearance and consistency. The stem
is 3 – long, 1 – thick, equal, tubular, somewhat elastic, cartilaginous, and not particularly fragile. The base of the stem is either strigose (covered with sharp, straight, stiff white hairs) or surrounded with a matted white mycelium
. Above the base, the stem is smooth, and pruinose toward the apex. When moist it is translucent with slight ripples running transversely, and white to pale yellow in color. Mycena flavoalba is considered inedible.
s are 7–9 by 3–4.5 μm
, ellipsoid, and nonamyloid
. The basidia (spore-bearing cells) are four-spored. The pleurocystidia and cheilocystidia (cystidia
found on the face and edge of a gill, respectively) are similar in structure and abundant, ventricose with long, rather narrow necks, and measure 46–62 by 9–14 μm. The neck is often encrusted with a mucilaginous substance, but it is otherwise smooth and hyaline
. The flesh of the gill is homogenous, and stains pale yellow in iodine. The flesh of the cap has a thin, poorly differentiated pellicle (a thin membrane), a somewhat differentiated hypoderm (that is most pronounced in old caps) and the remainder is made up of somewhat enlarged cells that stain pale yellow in iodine.
, such as H. lactea and H. delectabilis. It can be distinguished from these species by its white to yellowish cap, and differences in the shape of both its spores and caulocystidia (cystidia on the stem). H. conidiogena, a Spanish species newly described from in 2005, is also similar in appearance, but differs in the distribution of pigment
in the cap, and the differential staining in response to the dye cresyl blue—M. flavoalba is positive, while H. conidiogena is negative.
woods during the autumns months. Although generally rare, the species sometimes occurs in large quantities in certain localities. In the United States, it has been collected from Colorado
, Idaho
, Michigan
, North Carolina
, Oregon
, Washington, Wyoming
, Florida
, and Kansas
. It is also found in Europe, and Israel. The species is listed as "Least Concern" in the Danish Red Data Book
.
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...
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. The cap
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...
is initially conical in shape, before becoming convex and then flattening out; it may reach dimensions of up to 1.5 cm (0.590551181102362 in) across. The cap color is ivory-white to yellowish white, sometimes more yellowish at the center. The tubular 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 8 cm (3.1 in) long and 2.5 mm (0.0984251968503937 in) thick, and have long, coarse white hairs at their bases. The mushroom is found in Europe, the Middle East, and North America, where it grows scattered or in dense groups under conifers and on humus in oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
woods.
Taxonomy, classification, and naming
First described as Agaricus flavoalbus by Swedish mycologist Elias Magnus FriesElias Magnus Fries
-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...
in 1838, it was assigned its current name in 1872 by Lucien Quélet
Lucien Quélet
thumb|Lucien QuéletLucien Quélet was a French mycologist and naturalist who discovered several species and was the founder of the Société mycologique de France, a society devoted to mycological studies....
. American mycologist 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....
transferred the species to the genera Hemimycena
Hemimycena
Hemimycena is a genus of fungi in the family Mycenaceae. The genus has a widespread distribution, and contains about 50 species.-Species:*H. angustispora*H. candida*H. cephalotricha*H. conidiogena*H. crispata*H. cucullata...
and Marasmiellus
Marasmiellus
Marasmiellus is a genus of fungus in the Marasmiaceae family of mushrooms. The widespread genus, circumscribed by American mycologist William Murrill in 1915, contains about 250 species.The name comes from the Greek marasmus meaning wasting....
in 1938 and 1951, respectively. Singer later changed his mind about these placements, and his 1986 Agaricales in Modern Taxonomy, he considered the species a Mycena. The binomials resulting from these transfers are considered synonyms
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
; another synonym is Mycena luteoalba (Bolton) Gray.
Mycena flavoalba is placed in the section Adonideae of 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...
, alongside species such as and .
The specific epithet flavoalba ("yellow-white") is a compound of the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
adjectives flavus ("yellow) and alba ("white"). The mushroom's common name
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...
is the "ivory bonnet".
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...
of M. flavoalba is 1 – in diameter, conical when young, becoming somewhat bell-shaped, broadly conic or at times nearly convex. It may develop a papilla (a nipple-like structure) in its center. The cap margin is initially pressed against the stem, but in maturity either flares out or curves inward slightly. The cap surface is smooth, moist, and partially translucent, so that the outline of the gills underneath the cap may be seen. The mushroom is hygrophanous
Hygrophanous
The adjective hygrophanous refers to the color change of mushroom tissue as it loses or absorbs water, which causes the pileipellis to become more transparent when wet and opaque when dry....
(changing color as it loses or gains moisture), being cream-buff to yellowish initially, with a paler (almost white) margin, and fading to buff in the center and yellowish-white along the margin when dry. The flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
is yellowish to white, thick under the disc but otherwise thin, moderately fragile, and without any distinctive odor and taste.
The gills are ascending and somewhat hooked or toothed, narrow at first but becoming rather broad (2.5 mm and becoming 3–4 mm). They are nearly equal in width throughout or slightly ventricose
Ventricose
In mycology, Ventricose is a condition in which the cystidia, lamella or stipe of a mushroom is swollen in the middle....
in age, with a spacing that is close to subdistant. About 18–24 gills reach the stem, with two tiers of lamellulae (short gills that do not extend fully from the cap margin to the stem) that may develop veins running between them. The gills are white to creamy-white with edges that are even and whitish, and waxy in appearance and consistency. The 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...
is 3 – long, 1 – thick, equal, tubular, somewhat elastic, cartilaginous, and not particularly fragile. The base of the stem is either strigose (covered with sharp, straight, stiff white hairs) or surrounded with a matted white 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...
. Above the base, the stem is smooth, and pruinose toward the apex. When moist it is translucent with slight ripples running transversely, and white to pale yellow in color. Mycena flavoalba is considered inedible.
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 are 7–9 by 3–4.5 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...
, ellipsoid, and nonamyloid
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...
. The basidia (spore-bearing cells) are four-spored. The pleurocystidia and cheilocystidia (cystidia
Cystidium
A cystidium is a relatively large cell found on the hymenium of a basidiomycete , often between clusters of basidia. Since cystidia have highly varied and distinct shapes that are often unique to a particular species or genus, they are a useful micromorphological characteristic in the...
found on the face and edge of a gill, respectively) are similar in structure and abundant, ventricose with long, rather narrow necks, and measure 46–62 by 9–14 μm. The neck is often encrusted with a mucilaginous substance, but it is otherwise smooth and 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...
. The flesh of the gill is homogenous, and stains pale yellow in iodine. The flesh of the cap has a thin, poorly differentiated pellicle (a thin membrane), a somewhat differentiated hypoderm (that is most pronounced in old caps) and the remainder is made up of somewhat enlarged cells that stain pale yellow in iodine.
Similar species
Mycena flavoalba bears resemblance to some members of the genus HemimycenaHemimycena
Hemimycena is a genus of fungi in the family Mycenaceae. The genus has a widespread distribution, and contains about 50 species.-Species:*H. angustispora*H. candida*H. cephalotricha*H. conidiogena*H. crispata*H. cucullata...
, such as H. lactea and H. delectabilis. It can be distinguished from these species by its white to yellowish cap, and differences in the shape of both its spores and caulocystidia (cystidia on the stem). H. conidiogena, a Spanish species newly described from in 2005, is also similar in appearance, but differs in the distribution of 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...
in the cap, and the differential staining in response to the dye cresyl blue—M. flavoalba is positive, while H. conidiogena is negative.
Habitat and distribution
The fruit bodies of Mycena flavoalba grow scattered to densely gregarious on needle beds under conifers, and on humus in oakOak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
woods during the autumns months. Although generally rare, the species sometimes occurs in large quantities in certain localities. In the United States, it has been collected from Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
, Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
, Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, Washington, Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, and Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
. It is also found in Europe, and Israel. The species is listed as "Least Concern" in the Danish Red Data Book
Regional Red List
A Regional Red List is a report of the threatened status of species within a certain country or region. It is based on the IUCN Red List of Threatened Species, an inventory of the conservation status of species on a global scale...
.