Tricholoma sulphureum, also known as sulphur knight or gas agaric, is an inedible or mildly poisonous mushroom found in woodlands in Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

. It has a distinctive bright yellow colour and an unusual smell likened to coal gas. It occurs in deciduous woodlands in Europe from spring to autumn.

Taxonomy

Tricholoma sulphureum was first described in 1784 by the French botanist Pierre Bulliard

Jean Baptiste François Pierre Bulliard

Jean Baptiste François Pierre Bulliard was a French physician and botanist....

 and given the name Agaricus sulphureus, before being placed in the genus Tricholoma by German mycologist Paul Kummer

Paul Kummer

Paul Kummer was a priest, teacher, and scientist in Zerbst, Germany, known chiefly for his contribution to mycological nomenclature. Earlier classification of agarics by pioneering fungal taxonomist Elias Magnus Fries designated only a very small number of genera, with most species falling into...

 in 1871. The specific epithet sulfǔrěus derived from 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...

 'of or pertaining to sulfur

Sulfur

Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...

'. It belongs to a complex of similar foul-smelling species such as Tricholoma inamoenum. Another related species, T. bufonium, may be an intraspecific variant.

Description

It has a convex 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...

 with a vague 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...

 up to 8 cm (3 in) across, sulphur yellow in colour. The thick, sinuate gills, stipe

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...

 and 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....

 are similarly bright yellow. The smell, caused by the chemical skatole

Skatole

Skatole or 3-methylindole is a mildly toxic white crystalline organic compound belonging to the indole family. It occurs naturally in feces and coal tar, and has a strong fecal odor...

, is enough to distinguish it from other yellow fungi. John Ramsbottom

John Ramsbottom (mycologist)

John Ramsbottom was a British mycologist.He was Keeper of Botany at the British Museum . He served as general secretary and twice as president of the British Mycological Society, and was long editor of its Transactions. He was president of the Linnean Society from 1937 to 1940 and was awarded...

 reports that it has a complex smell that has been likened variously to Jasmine

Jasmine

Jasminum , commonly known as jasmines, is a genus of shrubs and vines in the olive family . It contains around 200 species native to tropical and warm temperate regions of the Old World...

, Narcissus, Hyacinth, Hemerocallis flava, Lilac

Lilac

Syringa is a genus of about 20–25 species of flowering woody plants in the olive family , native to woodland and scrub from southeastern Europe to eastern Asia, and widely and commonly cultivated in temperate areas elsewhere....

, Tagetes

Tagetes

Tagetes is a genus of 56 species of annual and perennial mostly herbaceous plants in the sunflower family . The genus is native to North and South America, but some species have become naturalized around the world. One species, T...

, decayed hemp

Hemp

Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

 or coal gas

Coal gas

Coal gas is a flammable gaseous fuel made by the destructive distillation of coal containing a variety of calorific gases including hydrogen, carbon monoxide, methane and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen...

, as well as described as nauseating or foetid. The taste is bitter.

It could be confused with the darker T. equestre

Tricholoma equestre

Tricholoma equestre or Tricholoma flavovirens, also known as Man on horseback or Yellow knight is a formerly widely eaten but hazardous fungus of the Tricholoma genus that forms ectomycorrhiza with pine trees....

, though the latter has a sticky cap, white flesh, thin crowded gills, and a mealy smell. However this latter species which was formerly considered a good edible mushroom

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...

, has itself caused cases of poisoning.

Distribution and habitat

Tricholoma sulphureum is found in deciduous

Deciduous

Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...

 woods, particularly beech

Beech

Beech is a genus of ten species of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America.-Habit:...

, and can occur anytime from spring until autumn. It is found across Europe and has been confirmed as far east as China.

Toxicity

The fungus is usually classified as inedible in guidebooks, although there have been reports of poisoning. Symptoms are predominantly gastrointestinal with some neurological.

External links

• “Tricholoma sulphureum” by Robert Sasata, Healing-Mushrooms.net, Mar, 2008.