''Galerina sulciceps'' is a dangerously toxic species of fungus in the family Strophariaceae, of the order

Agaricales The fungal order Agaricales, also known as gilled mushrooms (for their distinctive gills) or euagarics, contains some of the most familiar types of mushrooms. The order has 33 extant families, 413 genera, and over 13,000 described species, alo ...

. It is distributed in tropical Indonesia and India, but has reportedly been found fruiting in European greenhouses on occasion. More toxic than the deathcap (''Amanita phalloides''), ''G. sulciceps'' has been shown to contain the toxins alpha- (α-), beta- (β-) and gamma- (γ-) amanitin; 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 Mushroom hunting, mushrooming, mushroom picking, mushroom foraging, and similar terms describe the activity of gathering mushrooms in the wild, typically for culinary use. This practice is popular throughout most of Europe, Australia, Japan, ...

" appearance, with few obvious external characteristics to help distinguish it from many other similar nondescript brown species. The

fruit bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

of the fungus are tawny to

ochre Ochre ( ; , ), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colours produced ...

, deepening to reddish-brown at the base of the

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

. The gills are well-separated, and there is no

ring Ring may refer to: * Ring (jewellery), a round band, usually made of metal, worn as ornamental jewelry * To make a sound with a bell, and the sound made by a bell :(hence) to initiate a telephone connection Arts, entertainment and media Film and ...

present on the stem.

History and taxonomy

This species was first described in the literature as ''

Marasmius ''Marasmius'' is a genus of mushroom-forming fungi 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 ...

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 Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...

). In 1898,

Otto Kuntze Carl Ernst Otto Kuntze (23 June 1843 – 27 January 1907) 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 1866 he ...

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 Karel Bernard Boedijn (29 June 1893 – 29 August 1964) was a Dutch botanist and mycologist. Born in Amsterdam, he graduated with a PhD from the University of Amsterdam in 1925; his thesis was titled "Der Zusammenhang zwischen den Chromosomen und M ...

transferred the species to the genus ''

Phaeomarasmius ''Phaeomarasmius'' is a genus of fungi in the family Tubariaceae. It was formerly thought to belong in the family Inocybaceae The Inocybaceae are a family of fungi in the order Agaricales. Members of this family have a widespread distribution ...

'' 1938. In 1951, he redescribed the species and transferred it to its current position in '' Galerina''.

Rolf Singer Rolf Singer (June 23, 1906 – January 18, 1994) was a Germany, German-born mycologist and one of the most important Taxonomy (biology), taxonomists of gilled mushrooms (agarics) in the 20th century. After receiving his Ph.D. at the University ...

's comprehensive taxonomical treatment of the

placed ''Galerina sulciceps'' in section ''Naucoriopsis'' of the genus ''Galerina'', a subdivision first defined by French mycologist

Robert Kühner Robert Kühner (15 March 1903 in Paris – 27 February 1996 in Lyon) was a French mycologist most notable for reviewing many forms of agaric (mushroom fungus) genera. He studied at the Sorbonne, afterwards from 1921 until 1932, he was working ...

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 cap 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 , 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 Adnate may refer to: * Adnation, in botany, the fusion of two or more whorls of a flower * Adnate, in mycology, a classification of lamellae (gills) * Conjoined twins Conjoined twins – sometimes popularly referred to as Siamese twins – are ...

(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

is long, 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 Pruinescence , or pruinosity, is a "frosted" or dusty-looking coating on top of a surface. It may also be called a pruina (plural: ''pruinae''), from the Latin word for hoarfrost. The adjectival form is pruinose . Entomology In insects, a "blo ...

(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

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...

s are

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

to almond-shaped, with dimensions of 7.2–9.7 by 4.5–5.8

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

. 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 A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

) 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 A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

e of ''G. sulciceps'' have clamp connections—short branches connecting one cell to the previous cell to allow passage of the products of

nuclear Nuclear may refer to: Physics Relating to the nucleus of the atom: * Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear ...

division.

Biochemistry

''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 Dialysis may refer to: *Dialysis (chemistry), a process of separating molecules in solution **Electrodialysis, used to transport salt ions from one solution to another through an ion-exchange membrane under the influence of an applied electric pote ...

or liver transplants.

Habitat and distribution

This species grows on dead wood in tropical locales like Indonesia ( Java and

Sumatra Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...

), and near India (

), 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 Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

sawdust.

References