Amanita ravenelii
Encyclopedia
Amanita ravenelii, commonly known as the pinecone Lepidella, is a species of fungus
in the Amanitaceae
family. The fruit bodies are medium to large, with caps up to 17 cm (6.7 in) wide, and a stem up to 25 cm (9.8 in) long and 3 cm (1.2 in) thick. The warts on the whitish cap surface are large—up to 6 mm (0.236220472440945 in) wide and 4 mm (0.15748031496063 in) high. The stem has a large bulb at its base, covered with whitish to brownish scales, that may root several centimeters into the soil. The ring
on the stem is thick and cotton- or felt-like. It is widely distributed in mixed and deciduous forests of the southeastern United States, where it grows solitarily or in groups on the ground in late summer and autumn. The mushrooms, which have an odor resembling bleaching powder, are not recommended for consumption.
and Moses Ashley Curtis
in 1859 as Agaricus ravenelii. Pier Andrea Saccardo
transferred it to the genus Amanita
in 1887. It is in the subsection Solitariae, section Lepidella in the genus Amanita
. Other North American species in the section Lepidella include A. abrupta
, A. atkinsoniana
, A. chlorinosma, A. cokeri
, A. daucipes
, A. mutabilis, A. onusta
, A. pelioma, A. polypyramis, and A. rhopalopus.
The specific epithet ravenelli honors the American mycologist Henry William Ravenel
. The fungus is commonly
known as the "pinecone Lepidella".
is 8 – wide, initially hemispherical to almost round, later becoming convex to flattened. It is fleshy, white to yellowish-white, usually dry, but occasionally slightly sticky with age. The universal veil
remains as a pale yellow to brownish-orange layer that breaks up into crowded, rather coarse, conical to truncate-conical warts. The warts are up to 6 mm (0.236220472440945 in) wide and 4 mm (0.15748031496063 in) high, becoming more scale-like towards the cap margin with age. The margin is non-striate (without any grooves), and appendiculate (with partial veil
remnants hanging along the cap margin). The gills are free from attachment to the stem, crowded together, moderately broad, and yellowish-white to pale yellow. Interspersed among the gills are short gills (lamellulae) that do not extend completely to the stem; they are somewhat truncated (abruptly terminated) to attenuated (tapering gradually). The stem
is 10 – long and 1 – wide, and decreases slightly in thickness near the apex. It is solid (i.e., not hollow), white to pale yellow, and covered with tufts of soft woolly hairs or fibrils. It has a large basal bulb, swollen in the middle, which roots in the ground up to 5.5 cm (2.2 in). The partial veil is yellowish-white to pale yellow, forming an ring
which is thick, woolly, delicate, and soon falls away. The universal veil remains at the stem base as thick scales, curved downward, often forming irregular rings. The flesh
is firm, and white to pale yellow. The mushroom tissue has an odor of chlorinated lime (bleaching powder), or "old tennis shoes". The edibility
of Amanita ravenelii mushrooms have been described variously as unknown, "not recommended", or poisonous.
s are ellipsoid, occasionally ovoid or obovoid, thin-walled, hyaline
, amyloid
, and measure 8–11 by 5.5–7.5 µm. The spore deposit
is white. The basidia (spore-bearing cells) are 40–65 by 7–11.5 µm, four-spored, with clamps at their bases. Cheilocystidia (cystidia on the gill edge) are occasionally seen as small, club-shaped cells measuring 15–35 by 10–15 µm, on thin-walled hyphae that are 3–7 µm in diameter. The cap cuticle
, which is not clearly differentiated from the cap tissue, consists of thin-walled, interwoven hypha
e 2.5–9 µm in diameter. The tissue of the universal veil on the cap consists of more or less parallel and erect rows of roughly spherical, and ellipsoid to broadly ellipsoid cells, up to 78 by 65 µm and spindle- to club-shaped cells up to 125 by 30 µm. These latter cells are terminal or in short, terminal chains, and are borne on moderately abundant, thin-walled, branched, interwoven, sometimes nearly coralloid hyphae, 3–9.5 µm diameter with a few scattered oleiferous (oil-containing) hyphae, 5–12.5 µm diameter. The distribution of hyphae at the stem base is similar to that on the cap, but with more filamentous hyphae. Clamp connection
s are present.
and old growth Douglas fir. Also from North America, A. mutabilis has pink tones on the cap and stem, and will turn pink when its flesh is cut; it smells of anise
.
l fungus, meaning it forms mutualistic associations with shrubs and trees. Mushrooms grow on the ground solitarily, scattered, or in groups in mixed coniferous and deciduous forests. Although the specific tree associations preferred by A. ravenelii are unknown, in general, Amanita from section Lepidella tend to associate with diploxylon pine (that is, pines in subgenus Pinus
), oak
, and hickory
.
Amanita ravenelii is widely distributed in the southeastern United States, where their occurrence is "occasional to frequent" in the late summer and autumn months of August to November; mushrooms been collected from the US states of Maryland
, North Carolina
, South Carolina
, Tennessee
, and Virginia
. It has also been reported growing in northern Baja California
, Mexico.
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 Amanitaceae
Amanitaceae
Amanitaceae are a family of fungi or mushrooms. The family, also commonly called the Amanita family, is in order Agaricales, gilled mushrooms...
family. The fruit bodies are medium to large, with caps up to 17 cm (6.7 in) wide, and a stem up to 25 cm (9.8 in) long and 3 cm (1.2 in) thick. The warts on the whitish cap surface are large—up to 6 mm (0.236220472440945 in) wide and 4 mm (0.15748031496063 in) high. The stem has a large bulb at its base, covered with whitish to brownish scales, that may root several centimeters into the soil. The 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...
on the stem is thick and cotton- or felt-like. It is widely distributed in mixed and deciduous forests of the southeastern United States, where it grows solitarily or in groups on the ground in late summer and autumn. The mushrooms, which have an odor resembling bleaching powder, are not recommended for consumption.
Taxonomy
The species was first described scientifically by Miles Joseph BerkeleyMiles Joseph Berkeley
Miles Joseph Berkeley was an English cryptogamist and clergyman, and one of the founders of the science of plant pathology....
and Moses Ashley Curtis
Moses Ashley Curtis
Moses Ashley Curtis was a noted American botanist.Curtis was born in Stockbridge, Massachusetts and educated at Williams College in Massachusetts. After graduating, he became a tutor for the children of former Governor Edward Bishop Dudley in Wilmington, North Carolina, returning to Massachusetts...
in 1859 as Agaricus ravenelii. Pier Andrea Saccardo
Pier Andrea Saccardo
Pier Andrea Saccardo was an Italian botanist and mycologist.- Life :...
transferred it to the genus Amanita
Amanita
The genus Amanita contains about 600 species of agarics including some of the most toxic known mushrooms found worldwide. This genus is responsible for approximately 95% of the fatalities resulting from mushroom poisoning, with the death cap accounting for about 50% on its own...
in 1887. It is in the subsection Solitariae, section Lepidella in the genus Amanita
Amanita
The genus Amanita contains about 600 species of agarics including some of the most toxic known mushrooms found worldwide. This genus is responsible for approximately 95% of the fatalities resulting from mushroom poisoning, with the death cap accounting for about 50% on its own...
. Other North American species in the section Lepidella include A. abrupta
Amanita abrupta
Amanita abrupta, commonly known as the abrupt-bulbed Lepidella, is a species of fungus in the Amanitaceae family of mushrooms. Named for the characteristic shape of its fruit bodies, this white Amanita has a slender stem, a cap covered with conical white warts, and an "abruptly enlarged" swollen base...
, A. atkinsoniana
Amanita atkinsoniana
Amanita atkinsoniana is a species of fungus in the Amanitaceae family. It is found in the northeastern, southeastern, and southern United States as well as southern Canada, where it grows solitarily or in small groups on the ground in mixed woods. The fruit body is white to brownish, with caps that...
, A. chlorinosma, A. cokeri
Amanita cokeri
Amanita cokeri, commonly known as Coker's Amanita, is a mushroom in the Amanitaceae family. The mushroom is poisonous. First described as Lepidella cokeri in 1928, it was transferred to the genus Amanita in 1940.-Description:...
, A. daucipes
Amanita daucipes
Amanita daucipes is a species of fungus in the Amanitaceae family of the Agaricales order of mushrooms. Found exclusively in North America, the mushroom may be recognized in the field by the medium to large white caps with pale orange tints, and the dense covering of pale orange or reddish-brown...
, A. mutabilis, A. onusta
Amanita onusta
Amanita onusta, commonly known as the loaded Lepidella or the gunpowder Lepidella, is a species of fungus in the Amanitaceae family of mushrooms. It is characterized by its small to medium-sized fruit bodies that have white to pale gray caps crowded with roughly conical, pyramidal, or irregular...
, A. pelioma, A. polypyramis, and A. rhopalopus.
The specific epithet ravenelli honors the American mycologist Henry William Ravenel
Henry William Ravenel
Henry William Ravenel was a botanist of the United States. He studied fungi and cryptogams in South Carolina, discovering a large number of new species...
. The fungus 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 the "pinecone Lepidella".
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...
is 8 – wide, initially hemispherical to almost round, later becoming convex to flattened. It is fleshy, white to yellowish-white, usually dry, but occasionally slightly sticky with age. The universal veil
Universal veil
In mycology, a universal veil is a temporary membranous tissue that fully envelops immature fruiting bodies of certain gilled mushrooms. The developing Caesar's mushroom , for example, which may resemble a small white sphere at this point, is protected by this structure...
remains as a pale yellow to brownish-orange layer that breaks up into crowded, rather coarse, conical to truncate-conical warts. The warts are up to 6 mm (0.236220472440945 in) wide and 4 mm (0.15748031496063 in) high, becoming more scale-like towards the cap margin with age. The margin is non-striate (without any grooves), and appendiculate (with partial veil
Partial veil
thumb|150px|right|Developmental stages of [[Agaricus campestris]] showing the role and evolution of a partial veilPartial veil is a mycological term used to describe a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics...
remnants hanging along the cap margin). The gills are free from attachment to the stem, crowded together, moderately broad, and yellowish-white to pale yellow. Interspersed among the gills are short gills (lamellulae) that do not extend completely to the stem; they are somewhat truncated (abruptly terminated) to attenuated (tapering gradually). 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 10 – long and 1 – wide, and decreases slightly in thickness near the apex. It is solid (i.e., not hollow), white to pale yellow, and covered with tufts of soft woolly hairs or fibrils. It has a large basal bulb, swollen in the middle, which roots in the ground up to 5.5 cm (2.2 in). The partial veil is yellowish-white to pale yellow, forming an 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...
which is thick, woolly, delicate, and soon falls away. The universal veil remains at the stem base as thick scales, curved downward, often forming irregular rings. 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 firm, and white to pale yellow. The mushroom tissue has an odor of chlorinated lime (bleaching powder), or "old tennis shoes". 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 Amanita ravenelii mushrooms have been described variously as unknown, "not recommended", or poisonous.
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 ellipsoid, occasionally ovoid or obovoid, thin-walled, 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...
, 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...
, and measure 8–11 by 5.5–7.5 µm. The spore deposit
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. The basidia (spore-bearing cells) are 40–65 by 7–11.5 µm, four-spored, with clamps at their bases. Cheilocystidia (cystidia on the gill edge) are occasionally seen as small, club-shaped cells measuring 15–35 by 10–15 µm, on thin-walled hyphae that are 3–7 µm in diameter. The cap cuticle
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....
, which is not clearly differentiated from the cap tissue, consists of thin-walled, interwoven hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e 2.5–9 µm in diameter. The tissue of the universal veil on the cap consists of more or less parallel and erect rows of roughly spherical, and ellipsoid to broadly ellipsoid cells, up to 78 by 65 µm and spindle- to club-shaped cells up to 125 by 30 µm. These latter cells are terminal or in short, terminal chains, and are borne on moderately abundant, thin-walled, branched, interwoven, sometimes nearly coralloid hyphae, 3–9.5 µm diameter with a few scattered oleiferous (oil-containing) hyphae, 5–12.5 µm diameter. The distribution of hyphae at the stem base is similar to that on the cap, but with more filamentous hyphae. 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 are present.
Similar species
The fruit bodies of A. ravenelii are distinguished from A. chlorinosma by the presence of pale yellow to brownish orange, large, conical to truncate-conical warts on the cap surface and a large basal bulb. The mushroom A. polypyramis is pure white, and lacks the pale yellow to brownish-orange large conical warts typical of A. ravenelii. The North American species A. armillariiformis has a similar areolate cap surface, but unlike A. ravenelii, does not have a distinct basal bulb, and it is found in semi-arid areas associated with aspenAspen
Populus section Populus, of the Populus genus, includes the aspen trees and the white poplar Populus alba. The five typical aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. The White Poplar, by...
and old growth Douglas fir. Also from North America, A. mutabilis has pink tones on the cap and stem, and will turn pink when its flesh is cut; it smells of anise
Anise
Anise , Pimpinella anisum, also called aniseed, is a flowering plant in the family Apiaceae native to the eastern Mediterranean region and Southwest Asia. Its flavor resembles that of liquorice, fennel, and tarragon.- Biology :...
.
Habitat and distribution
Amanita ravenelii is a mycorrhizaMycorrhiza
A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....
l fungus, meaning it forms mutualistic associations with shrubs and trees. Mushrooms grow on the ground solitarily, scattered, or in groups in mixed coniferous and deciduous forests. Although the specific tree associations preferred by A. ravenelii are unknown, in general, Amanita from section Lepidella tend to associate with diploxylon pine (that is, pines in subgenus Pinus
Pinus classification
There are three main subgenera of Pinus, the subgenus Strobus , the subgenus Ducampopinus , and the subgenus Pinus...
), 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...
, and hickory
Hickory
Trees in the genus Carya are commonly known as hickory, derived from the Powhatan language of Virginia. The genus includes 17–19 species of deciduous trees with pinnately compound leaves and big nuts...
.
Amanita ravenelii is widely distributed in the southeastern United States, where their occurrence is "occasional to frequent" in the late summer and autumn months of August to November; mushrooms been collected from the US states of Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, 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...
, South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
, and Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
. It has also been reported growing in northern Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
, Mexico.