Galerina sulciceps
Encyclopedia
Galerina sulciceps is a dangerously toxic
species of fungus
in the family Strophariaceae
, of the order Agaricales
. It is distributed in tropical Indonesia and India, but has reportedly been found fruiting in European greenhouses on occasion. Considered more deadly than the deathcap (Amanita phalloides), G. sulciceps has been shown to contain the toxins known as alpha-
(α-), beta-
(β-) and gamma-
(γ-) amanitins; a series of poisonings in Indonesia in the 1930s resulted in 14 deaths from the consumption of this species. It has a typical "little brown mushroom" appearance, with few obvious external characteristics to help distinguish it from many other similar nondescript brown species. The fruit bodies
of the fungus are tawny
to ochre
, deepening to reddish-brown at the base of the stem
. The gills are well-separated, and there is no ring
present on the stem.
sulciceps by English Naturalist Miles Joseph Berkeley
in 1848, based on a specimen found four years earlier growing on old wood in Ceylon (modern-day Sri Lanka
). In 1898, Otto Kuntze
transferred the species to Chamaeceras, a genus that has since been subsumed back into Marasmius. Because of its brown-colored spore print
, Dutch mycologist Karel Bernard Boedijn transferred the species to the genus Phaeomarasmius
1938. In 1951, he redescribed the species and transferred it to its current position in Galerina
. Rolf Singer
's comprehensive taxonomical
treatment of the Agaricales
placed Galerina sulciceps in section Naucoriopsis of the genus Galerina, a subdivision first defined by French mycologist Robert Kühner
in 1935. This section includes small brown-spored fungi what when young have a cap margin that is curved inward, and thin-walled, obtuse, or acute-ended pleurocystidia that are not broadly rounded at the top. All of the poisonous amatoxin-containing Galerina belong to section Naucoriopsis.
is initially egg-shaped in young specimens, but changes shape as it matures, becoming convex and later more or less flat with a central depression. At the center of the cap is a roughly spherical umbo
– a nipple-like protrusion. The cap is hygrophanous
, meaning it changes color depending on its state of hydration: the color is tawny in moist specimens, changing to ochre with dark brown edges when dried. The cap diameter is typically 1.5 to 4 cm (0.590551181102362 to 1.6 in), with a surface that is smooth, and almost gelatinous in consistency. The edge of the cap is thin and wavy, and is often split open. The gills are broadly adnate (broadly attached to the stalk slightly above the bottom of the gill, with most of the gill fused to the stem) to slightly decurrent (running down the length of the stem). Interspersed between the gills are shorter gills, called lamellulae, that start from the cap but do not reach the stem. The gills are broad (up to 4 mm) and thick at the base (1 mm), and when mature can develop veins that run between the gills on the undersurface of the cap. The stem
is 0.4 to 2.5 cm (0.15748031496063 to 0.984251968503937 in) long, 0.15 to 0.3 cm (0.0590551181102362 to 0.118110236220472 in) thick, and usually attached centrally to the underside of the cap, although it may sometimes be slightly off-center. Stems are solid, cylindrical, and may be pruinose: dusted with a very fine layer of powder.
Berkeley's original description noted a resemblance to a small Marasmius peronatus, a mushroom today known as Gymnopus peronatus.
s are ellipsoid to almond-shaped, with dimensions of 7.2–9.7 by 4.5–5.8 µm
. The basidia
(spore-bearing cells) are cylindrical to slightly club-shaped, four-spored, and measure 30–45 by 5.5–6 µm. The sterigmata (projections of the basidia that attach the spores) are 5–6 µm long. The pleurocystidia (cystidia located in the gill face) are thin-walled, with long, somewhat cylindrical necks, and may range in color from translucent (hyaline
) to pale brownish-yellow. They are typically 40 by 10.5 µm, although they may occasionally be larger—up to 142 by 18 by 8 µm. Cystidia in the gill edge—the cheilocystidia—are similar in appearance to the pleurocystidia. The hypha
e of G. sulciceps have clamp connection
s—short branches connecting one cell to the previous cell to allow passage of the products of nuclear
division.
Galerina sulciceps is deadly poisonous; one author opines it to be "perhaps the most toxic mushroom known to man", while later studies of toxin concentrations in amanitin-containing mushrooms corroborate this view. The symptoms of poisoning attributed to the mushroom have been noted to be relatively unusual: a local anesthesic effect, "pins and needles" sensation, and nausea without vomiting. Although these clinical symptoms are inconsistent with those of amatoxin
poisoning, the presence of α-
, β-
and γ-
amanitins in this species has been verified with chromatographic analysis
. Amatoxins damage the liver
and kidney
by binding irreversibly to RNA polymerase II
. Three separate instances of poisoning in Indonesia involved 18 people, 14 of which died. Based on this set of occurrences, death occurs in 7–51 hours "unless the patient survives, which seems to depend on the quantity eaten and the vigor of the individual." Another death attributed to this mushroom was reported in Germany in the early 1980s. Severe poisonings have been treated with complete blood dialysis
or liver transplants.
and Sumatra
), and India (Sri Lanka
), where it is prolific in some areas. It is not found in North America. In Germany, it has been found growing in greenhouses, and is known in the vernacular
as the Gewächshaus-Häubling, meaning "greenhouse Galerina". In one instance, the mushroom was discovered fruiting in dense groups in pots of orchids standing on moist conifer sawdust.
Mushroom poisoning
Mushroom poisoning refers to harmful effects from ingestion of toxic substances present in a mushroom. These symptoms can vary from slight gastrointestinal discomfort to death. The toxins present are secondary metabolites produced in specific biochemical pathways in the fungal cells...
species of fungus
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 family Strophariaceae
Strophariaceae
The Strophariaceae are a family of fungi in the order Agaricales. The family contains 18 genera and 1316 species. The species of Strophariaceae have a red-brown to dark brown spore print, while the spores themselves are smooth and have an apical germ pore. These agarics are also characterized by...
, of the order Agaricales
Agaricales
The fungal order Agaricales, also known as gilled mushrooms , or euagarics, contains some of the most familiar types of mushrooms. The order has 33 extant families, 413 genera, and over 13000 described species, along with five extinct genera known only from the fossil record...
. It is distributed in tropical Indonesia and India, but has reportedly been found fruiting in European greenhouses on occasion. Considered more deadly than the deathcap (Amanita phalloides), G. sulciceps has been shown to contain the toxins known as alpha-
Alpha-amanitin
alpha-Amanitin or α-amanitin is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally A....
(α-), beta-
Beta-amanitin
beta-Amanitin or β-amanitin is a cyclic peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in several members of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally A. virosa...
(β-) and gamma-
Gamma-amanitin
gamma-Amanitin or γ-amanitin is a cyclic peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in several members of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally...
(γ-) amanitins; a series of poisonings in Indonesia in the 1930s resulted in 14 deaths from the consumption of this species. It has a typical "little brown mushroom" appearance, with few obvious external characteristics to help distinguish it from many other similar nondescript brown species. The fruit bodies
Basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
of the fungus are tawny
Tawny (color)
Tawny is a yellowish brown color. The word means "tan-colored," from Anglo-Norman tauné "associated with the brownish-yellow of tanned leather," from Old French tané "to tan hides," from Medieval Latin tannare, from tannum "crushed oak bark," used in tanning leather, probably from a Celtic source...
to ochre
Ochre
Ochre is the term for both a golden-yellow or light yellow brown color and for a form of earth pigment which produces the color. The pigment can also be used to create a reddish tint known as "red ochre". The more rarely used terms "purple ochre" and "brown ochre" also exist for variant hues...
, deepening to reddish-brown at the base of 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...
. The gills are well-separated, and there is no 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...
present on the stem.
History and taxonomy
This species was first described in the literature as MarasmiusMarasmius
Marasmius is a genus of mushrooms, in the family Marasmiaceae. It contains about 500 species of agarics, of which a few, such as Marasmius oreades, are edible. However, most members of this genus are small, unimpressive brown mushrooms...
sulciceps by English Naturalist Miles Joseph Berkeley
Miles Joseph Berkeley
Miles Joseph Berkeley was an English cryptogamist and clergyman, and one of the founders of the science of plant pathology....
in 1848, based on a specimen found four years earlier growing on old wood in Ceylon (modern-day Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
). In 1898, Otto Kuntze
Otto Kuntze
Otto Carl Ernst Kuntze was a German botanist.-Biography:Otto Kuntze was born in Leipzig.An apothecary in his early career, he published an essay entitled Pocket Fauna of Leipzig. Between 1863 and...
transferred the species to Chamaeceras, a genus that has since been subsumed back into Marasmius. Because of its brown-colored 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...
, Dutch mycologist Karel Bernard Boedijn transferred the species to the genus Phaeomarasmius
Phaeomarasmius
Phaeomarasmius is a genus of fungi in the Inocybaceae family. The genus has a widespread distribution, and contains about 20 species....
1938. In 1951, he redescribed the species and transferred it to its current position in Galerina
Galerina
Galerina is a genus of small brown-spored saprobic mushrooms, with over 300 species found throughout the world, from the far north to remote Macquarie Island in the Southern Ocean. Species are typically small and hygrophanous, with a slender and brittle stem. They are often found growing on wood,...
. 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....
's comprehensive taxonomical
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...
treatment of the Agaricales
Agaricales
The fungal order Agaricales, also known as gilled mushrooms , or euagarics, contains some of the most familiar types of mushrooms. The order has 33 extant families, 413 genera, and over 13000 described species, along with five extinct genera known only from the fossil record...
placed Galerina sulciceps in section Naucoriopsis of the genus Galerina, a subdivision first defined by French mycologist Robert Kühner
Robert Kühner
Robert Kühner, born Paris 15 March 1903, died Lyon 27 February 1996, was a French mycologist most notable for reviewing many agaric genera.-References:...
in 1935. This section includes small brown-spored fungi what when young have a cap margin that is curved inward, and thin-walled, obtuse, or acute-ended pleurocystidia that are not broadly rounded at the top. All of the poisonous amatoxin-containing Galerina belong to section Naucoriopsis.
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 initially egg-shaped in young specimens, but changes shape as it matures, becoming convex and later more or less flat with a central depression. At the center of the cap is a roughly spherical umbo
Umbo (mycology)
thumb|right|[[Cantharellula umbonata]] has an umbo.thumb|right|The cap of [[Psilocybe makarorae]] is acutely papillate.An umbo is a raised area in the center of a mushroom cap. Caps that possess this feature are called umbonate. Umbos that are sharply pointed are called acute, while those that are...
– a nipple-like protrusion. The cap 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....
, meaning it changes color depending on its state of hydration: the color is tawny in moist specimens, changing to ochre with dark brown edges when dried. The cap diameter is typically 1.5 to 4 cm (0.590551181102362 to 1.6 in), with a surface that is smooth, and almost gelatinous in consistency. The edge of the cap is thin and wavy, and is often split open. The gills are broadly adnate (broadly attached to the stalk slightly above the bottom of the gill, with most of the gill fused to the stem) to slightly decurrent (running down the length of the stem). Interspersed between the gills are shorter gills, called lamellulae, that start from the cap but do not reach the stem. The gills are broad (up to 4 mm) and thick at the base (1 mm), and when mature can develop veins that run between the gills on the undersurface of the cap. 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 0.4 to 2.5 cm (0.15748031496063 to 0.984251968503937 in) long, 0.15 to 0.3 cm (0.0590551181102362 to 0.118110236220472 in) thick, and usually attached centrally to the underside of the cap, although it may sometimes be slightly off-center. Stems are solid, cylindrical, and may be pruinose: dusted with a very fine layer of powder.
Berkeley's original description noted a resemblance to a small Marasmius peronatus, a mushroom today known as Gymnopus peronatus.
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 to almond-shaped, with dimensions of 7.2–9.7 by 4.5–5.8 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...
. The basidia
Basidium
thumb|right|500px|Schematic showing a basidiomycete mushroom, gill structure, and spore-bearing basidia on the gill margins.A basidium is a microscopic, spore-producing structure found on the hymenophore of fruiting bodies of basidiomycete fungi. The presence of basidia is one of the main...
(spore-bearing cells) are cylindrical to slightly club-shaped, four-spored, and measure 30–45 by 5.5–6 µm. The sterigmata (projections of the basidia that attach the spores) are 5–6 µm long. The pleurocystidia (cystidia located in the gill face) are thin-walled, with long, somewhat cylindrical necks, and may range in color from translucent (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...
) to pale brownish-yellow. They are typically 40 by 10.5 µm, although they may occasionally be larger—up to 142 by 18 by 8 µm. Cystidia in the gill edge—the cheilocystidia—are similar in appearance to the pleurocystidia. The 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 of G. sulciceps 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—short branches connecting one cell to the previous cell to allow passage of the products of nuclear
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
division.
Chemistry and toxicology
Amatoxin
Amatoxins are a subgroup of at least eight toxic compounds found in several genera of poisonous mushrooms, most notably Amanita phalloides and several other members of the genus Amanita, as well as some Conocybe, Galerina and Lepiota mushroom species.-Structure:The compounds have a similar...
poisoning, the presence of α-
Alpha-amanitin
alpha-Amanitin or α-amanitin is a cyclic peptide of eight amino acids. It is possibly the most deadly of all the amatoxins, toxins found in several species of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally A....
, β-
Beta-amanitin
beta-Amanitin or β-amanitin is a cyclic peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in several members of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally A. virosa...
and γ-
Gamma-amanitin
gamma-Amanitin or γ-amanitin is a cyclic peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in several members of the Amanita genus of mushrooms, one being the Death cap as well as the Destroying angel, a complex of similar species, principally...
amanitins in this species has been verified with chromatographic analysis
Chromatography
Chromatography is the collective term for a set of laboratory techniques for the separation of mixtures....
. Amatoxins damage the liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
and kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
by binding irreversibly to RNA polymerase II
RNA polymerase II
RNA polymerase II is an enzyme found in eukaryotic cells. It catalyzes the transcription of DNA to synthesize precursors of mRNA and most snRNA and microRNA. A 550 kDa complex of 12 subunits, RNAP II is the most studied type of RNA polymerase...
. Three separate instances of poisoning in Indonesia involved 18 people, 14 of which died. Based on this set of occurrences, death occurs in 7–51 hours "unless the patient survives, which seems to depend on the quantity eaten and the vigor of the individual." Another death attributed to this mushroom was reported in Germany in the early 1980s. Severe poisonings have been treated with complete blood dialysis
Dialysis
In medicine, dialysis is a process for removing waste and excess water from the blood, and is primarily used to provide an artificial replacement for lost kidney function in people with renal failure...
or liver transplants.
Habitat and distribution
This species grows on dead wood in tropical locales like Indonesia (JavaJava
Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...
and Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
), and India (Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
), where it is prolific in some areas. It is not found in North America. In Germany, it has been found growing in greenhouses, and is known in the vernacular
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...
as the Gewächshaus-Häubling, meaning "greenhouse Galerina". In one instance, the mushroom was discovered fruiting in dense groups in pots of orchids standing on moist conifer sawdust.