''Protostropharia semiglobata'', commonly known as the hemispherical stropharia, the dung roundhead, or the halfglobe mushroom, is an

agaric An agaric () is a type of fungal fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. It is a type of mushroom (or toadstool) ...

fungus of the family

Strophariaceae The Strophariaceae are a family of fungi in the order Agaricales. Under an older classification, the family covered 18 genera and 1316 species. The species of Strophariaceae have red-brown to dark brown spore prints, while the spores themselves a ...

. The mushrooms have hemispherical straw yellow to

buff Buff or BUFF may refer to: People * Buff (surname), a list of people * Buff (nickname), a list of people * Johnny Buff, ring name of American world champion boxer John Lisky (1888–1955) * Buff Bagwell, a ring name of American professional wr ...

- tan

caps Caps are flat headgear. Caps or CAPS may also refer to: Science and technology Computing * CESG Assisted Products Service, provided by the U.K. Government Communications Headquarters * Composite Application Platform Suite, by Java Caps, a Java ...

measuring , greyish

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

that become dark brown in age, and a slender, smooth

stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...

long with a fragile

ring (The) Ring(s) 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 Arts, entertainment, and media Film and TV * ''The Ring'' (franchise), a ...

. A common and widespread species with a

cosmopolitan distribution In biogeography, a cosmopolitan distribution is the range of a taxon that extends across most or all of the surface of the Earth, in appropriate habitats; most cosmopolitan species are known to be highly adaptable to a range of climatic and en ...

, the fungus produces

mushroom A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the n ...

s on the dung of various wild and domesticated

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

s. Accounts differ as to whether it is edible or perhaps poisonous.

Taxonomy

The species was first described as ''Agaricus semiglobatus'' by

August Batsch August Johann Georg Karl Batsch (28 October 1761 – 29 September 1802) was a German naturalist. He was a recognised authority on mushrooms, and also described new species of ferns, bryophytes, and seed plants. Life and career Batsch was born ...

in 1786. It has had a complicated

taxonomic 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation ...

history, having been shuffled to many different genera. In addition to ''Agaricus'' the species has been placed in ''

Coprinus ''Coprinus'' is a small genus of mushroom-forming fungi consisting of '' Coprinus comatus''the shaggy ink cap (British) or shaggy mane ( American)and several of its close relatives. Until 2001, ''Coprinus'' was a large genus consisting of all a ...

'', '' Geophila'', ''

Psalliota ''Agaricus'' is a genus of mushroom-forming fungi containing both edible and poisonous species, with over 400 members worldwide and possibly again as many disputed or newly discovered species. The genus includes the common ("button") mushroom (' ...

'', and ''

Psilocybe ''Psilocybe'' ( ) is a genus of gilled mushrooms, growing worldwide, in the family Hymenogastraceae. Many species contain the Psychedelic drug, psychedelic compounds psilocybin and psilocin. Taxonomy Taxonomic history A 2002 study of the ...

''. French mycologist

Lucien Quélet Lucien Quélet (; 14 July 1832 – 25 August 1899) was a French natural history, naturalist and mycologist. Quélet discovered several species of fungi and was the founder of the Société mycologique de France, a society devoted to mycological ...

gave it its most commonly used name in 1872 when he transferred it to ''

Stropharia The genus ''Stropharia'' (sometimes known by the common name roundheads) is a group of medium to large agarics with a distinct membranous ring on the stipe. Well-known members of this genus include the edible '' Stropharia rugosoannulata'' and t ...

''. In 2013, Scott Redhead made it the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

of ''

Protostropharia ''Protostropharia'', is a coprophilous agaric fungal genus that produces glutinous, mostly yellowish to yellow brown fruit bodies. Characteristically most form chrysocystidia and rather large, smooth, violaceous basidiospores each with a promin ...

'', a new genus circumscribed to contain ''Stropharia'' species characterized by the formation of astrocystidia rather than

acanthocytes Acanthocyte (from the Greek word ἄκανθα ''acantha'', meaning 'thorn'), in biology and medicine, refers to an abnormal form of red blood cell that has a spiked cell membrane, due to thorny projections. A similar term is spur cells. Often ...

on their

mycelium Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are fo ...

. A

form Form is the shape, visual appearance, or configuration of an object. In a wider sense, the form is the way something happens. Form may also refer to: *Form (document), a document (printed or electronic) with spaces in which to write or enter dat ...

''sterilis'' and two

varieties Variety may refer to: Arts and entertainment Entertainment formats * Variety (radio) * Variety show, in theater and television Films * ''Variety'' (1925 film), a German silent film directed by Ewald Andre Dupont * ''Variety'' (1935 film), ...

, ''minor'' and ''radicata'', described by F.H. Møller in 1945, are no longer considered to have independent taxonomic significance. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

''semiglobata'' is

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

for "half-spherical", and refers to the shape of the cap. It is commonly known as the halfglobe mushroom, the hemispheric stropharia, the round stropharia, or the dung roundhead.

Description

The

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. The origin of the word "cap" comes from the Old French word "chapeau" which means "head co ...

is obtuse to hemispherical in shape, reaching a diameter of . The cap surface is smooth and sticky, and initially has a light yellow color that fades in maturity to dull yellow or whitish. The

usually have an adnate attachment to the stem with a slight decurrent tooth. They are initially grayish, but become purplish brown to black, with white and fringed edges. They are distantly spaced and broad–about 6–8 mm; mature gills become ventricose (swollen). The

is long by thick, with a bulbous base. Initially filled with a cottony pith, the stem becomes hollow in maturity. A delicate

forms an annular zone on the mid to upper portion of the stem that may be darkened from spore deposits. Above the annular zone, the stem is covered with fine silk-like hairs; below, it is sticky. The stem tissue is white with a yellowish pith. The flesh has no distinctive odor, and a taste that is mild to slightly bitter. The mushroom produce a dark purple

spore print 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing warm orange ("tussock") color spore print. ...

. The thick-walled

spores In biology, a spore is a unit of sexual (in fungi) 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 plant ...

are ellipsoidal, smooth, and have a small apical

germ pore A germ pore is a small pore in the outer wall of a fungal spore through which the germ tube exits upon germination. It can be wikt:apical, apical or eccentric in its location, and, on light microscopy, may be visualized as a lighter coloured are ...

; they measure 16.1–19.0 by 8.8–11.0

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

. The

basidia A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

(spore-bearing cells) are four-spored, club-shaped,

hyaline A hyaline substance is one with a glassy appearance. The word is derived from , and . Histopathology Hyaline cartilage is named after its glassy appearance on fresh gross pathology. On light microscopy of H&E stained slides, the extracellula ...

(translucent), and measure 33–40 by 13–14.6 μm.

Similar species

Microscopy may be needed to distinguish the species from members of its genus. Other lookalikes include '' Agrocybe pediades'', ''

Panaeolus semiovatus ''Panaeolus'' is a genus of small, black-spored, saprotrophic agarics. The word ''Panaeolus'' is Greek for "all variegated", alluding to the spotted gills of the mushrooms produced. Characteristics These fungi are mostly dung and grassland sp ...

'', '' Stropharia dorsispora'', and '' S. luteonitens''.

Habitat and distribution

saprobic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ...

species, the fungus fruits in small groups on dung, in soil containing manure, on lawns, grasslands, or in livestock corrals. It has been recorded on the dung of a variety of wild and domesticated

s and

ungulate Ungulates ( ) are members of the diverse clade Euungulata ("true ungulates"), which primarily consists of large mammals with Hoof, hooves. Once part of the clade "Ungulata" along with the clade Paenungulata, "Ungulata" has since been determined ...

s, including rabbit, sheep, cow, buffalo, moose, bear, and wallaby. In some instances, the dung substrate is under

moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

so that it appears as if the mushroom is growing from the moss. Fruits bodies sometimes occur with another dung-loving fungus, ''

Deconica coprophila ''Deconica coprophila'', commonly known as the dung-loving psilocybe, meadow muffin mushroom, or dung demon, is a species of mushroom in the family Strophariaceae. Taxonomy First described as ''Agaricus coprophilus'' by Jean Baptiste Françoi ...

''. A widespread and common species, ''P. semiglobosa'' has a

, having been recorded from northern Asia, Australia, Europe, Central and South America, North America, North Africa, and New Zealand. It is thought to have been introduced to Australia with imported domestic stock.

Edibility

The fruit bodies have been listed as

edible An edible item is any item that is safe for humans to eat. "Edible" is differentiated from " eatable" because it does not indicate how an item tastes, only whether it is fit to be eaten. Nonpoisonous items found in nature – such as some mushroo ...

by some authors, but

poisonous A poison is any chemical substance that is harmful or lethal to living organisms. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figurati ...

by others. Even when not toxic, mushrooms that grow on dung are usually considered unpalatable, though the common mushroom is a counter-example.

References

External links

* {{Taxonbar, from=Q46810615 Strophariaceae Fungi of Africa Fungi of Asia Fungi of Australia Fungi of Central America Fungi of Europe Fungi of New Zealand Fungi of North America Fungi of South America Fungi described in 1786 Taxa named by August Batsch Fungus species