False morel

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A false morel is a fungus which looks very similar to a morel or Morchella Gyromitra Colima.jpg
A false morel is a fungus which looks very similar to a morel or Morchella

The name false morel is given to several species of mushroom which bear a resemblance to the highly regarded true morels of the genus Morchella . Like Morchella, false morels are members of the Pezizales, but within that group represent several unrelated taxa scattered through the families Morchellaceae, Discinaceae, and Helvellaceae, with the epithet "false morel" most often ascribed to members of the genus Gyromitra .

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Compared to morels

Gyromitra esculenta, a false morel Fruhjahrslorchel.JPG
Gyromitra esculenta, a false morel

When gathering morels for mushrooms, care must be taken to distinguish them from potentially poisonous lookalikes. While a great many morel lookalikes, and even morels themselves are toxic or cause gastrointestinal upset when consumed raw, some, such as Gyromitra esculenta remain toxic even after conventional cooking methods. Although some false morels can be eaten without ill effect, others can cause severe gastrointestinal upset, loss of muscular coordination (including cardiac muscle), or even death. [1] [2] Incidents of poisoning usually occur when they are eaten in large quantities, inadequately cooked, or over several days in a row. Some species contain gyromitrin, a toxic and carcinogenic organic compound, which is hydrolyzed in the body into monomethylhydrazine (MMH). [3] Gyromitra esculenta in particular has been reported to be responsible for up to 23% of mushroom fatalities each year in Poland. [4] G. esculenta—regarded as delicious—is known to be potentially deadly when eaten fresh, but research in the 1990s showed that toxins remain even after proper treatment. [5] [6] While many people freely eat false morels, potentially even toxic species, without apparent harm, some people have developed acute toxicity and recent evidence suggests that there may be long-term health risks as well. [7] [8]

The key morphological features distinguishing some of the false morels from true morels are as follows:

See also

Related Research Articles

Edible mushroom Fleshy and edible fruit bodies of many species of macrofungi

Edible mushrooms are the fleshy and edible fruit bodies of several species of macrofungi. They can appear either below ground (hypogeous) or above ground (epigeous) where they may be picked by hand. Edibility may be defined by criteria that include absence of poisonous effects on humans and desirable taste and aroma. Edible mushrooms are consumed for their nutritional and culinary value. Mushrooms, especially dried shiitake, are sources of umami flavor.

<i>Morchella</i> Genus of fungi

Morchella, the true morels, is a genus of edible sac fungi closely related to anatomically simpler cup fungi in the order Pezizales. These distinctive fungi have a honeycomb appearance due to the network of ridges with pits composing their caps. Morels are prized by gourmet cooks, particularly in Catalan and French cuisine. Due to difficulties in cultivation, commercial harvesting of wild morels has become a multimillion-dollar industry in the temperate Northern Hemisphere, in particular North America, Turkey, China, the Himalayas, India, and Pakistan where these highly prized fungi are found in abundance.

Mushroom hunting Activity of gathering mushrooms in the wild

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, Korea, parts of the Middle East, and the Indian subcontinent, as well as the temperate regions of Canada and the United States.

<i>Gyromitra esculenta</i> Species of fungus

Gyromitra esculenta is an ascomycete fungus from the genus Gyromitra, widely distributed across Europe and North America. It normally fruits in sandy soils under coniferous trees in spring and early summer. The fruiting body, or mushroom, is an irregular brain-shaped cap dark brown in colour that can reach 10 centimetres high and 15 cm (6 in) wide, perched on a stout white stipe up to 6 cm high.

Gyromitrin is a toxin and carcinogen present in several members of the fungal genus Gyromitra, like G. esculenta. Its formula is CH3CH=N−N(CH3)CHO. It is unstable and is easily hydrolyzed to the toxic compound monomethylhydrazine CH3NHNH2. Monomethylhydrazine acts on the central nervous system and interferes with the normal use and function of vitamin B6. Poisoning results in nausea, stomach cramps, and diarrhea, while severe poisoning can result in convulsions, jaundice, or even coma or death. Exposure to monomethylhydrazine has been shown to be carcinogenic in small mammals.

Mushroom poisoning Harmful effects from ingestion of toxic substances present in a mushroom

Mushroom poisoning is poisoning resulting from the ingestion of mushrooms that contain toxic substances. Its symptoms can vary from slight gastrointestinal discomfort to death in about 10 days. Mushroom toxins are secondary metabolites produced by the fungus.

<i>Morchella esculenta</i> Species of fungus

Morchella esculenta, is a species of fungus in the family Morchellaceae of the Ascomycota. It is one of the most readily recognized of all the edible mushrooms and highly sought after. Each fruit body begins as a tightly compressed, grayish sponge with lighter ridges, and expands to form a large yellowish sponge with large pits and ridges raised on a large white stem. The pitted yellow-brown caps measure 2–7 centimetres broad by 2–10 cm (1–4 in) tall, and are fused to the stem at its lower margin, forming a continuous hollow. The pits are rounded and irregularly arranged. The hollow stem is typically 2–9 cm long by 2–5 cm (1–2 in) thick, and white to yellow. The fungus fruits under hardwoods and conifers during a short period in the spring, depending on the weather, and is also associated with old orchards, woods and disturbed grounds.

<i>Gyromitra gigas</i> Species of fungus

Gyromitra gigas, commonly known as the giants false morel, snow morel, snow false morel, calf brain, or bull nose, is a fungus and a member of the Ascomycota. G. gigas is found in Europe. It is referred to as one of the false morels, due to its similar appearance and occurrence in the spring and early summer in similar habitats to true morels. It contains small quantities of hydrazines, its content in gyromitrin was scientifically assess by Viernstein et al. [Botanical identification 1980] and resulted of about 1mg per kg of fresh mushroom. No casualties have been ascribed to its consumption, parboiling is still highly recommended. Some guides have listed it as being edible if properly prepared. However, consumption is not recommended due to variability and similarity to other more toxic species of Gyromitra.

<i>Gyromitra</i> Genus of fungi

Gyromitra is a genus of about 18 species of ascomycete fungi. They are a false morel - a frequently toxic mushroom that can be mistaken for edible mushrooms of the genus Morchella (morels).

<i>Gyromitra infula</i> Species of fungus in the family Helvellaceae

Gyromitra infula, commonly known as the hooded false morel or the elfin saddle, is a fungus in the family Helvellaceae. The dark reddish-brown caps of the fruit bodies develop a characteristic saddle-shape in maturity, and the ends of both saddle lobes are drawn out to sharp tips that project above the level of the fruit body. The stipe is white or flushed pale brown, smooth on the outside, but hollow with some chambers inside. It is found in the Northern Hemisphere, usually in the late summer and autumn, growing on rotting wood or on hard packed ground. G. infula is considered inedible as it contains the toxic compound gyromitrin which, when metabolized by the body, is converted into monomethylhydrazine, a component of some rocket fuels. The toxin may be removed by thorough cooking. Gyromitra fungi are included in the informal category "false morels".

<i>Gyromitra ambigua</i> Species of fungus

Gyromitra ambigua is an ascomycete fungus species of the genus Gyromitra, and related to the false morel G. esculenta. It belongs to the Pezizales order. The species is found in North America, where it produces fruit bodies (mushrooms) that grow on the ground. The edibility of the fruit bodies is not known with certainty, and it is not recommended for consumption.

<i>Gyromitra caroliniana</i> Species of fungus

Gyromitra caroliniana, known commonly as the Carolina false morel or big red, is an ascomycete fungus of the genus Gyromitra, within the Pezizales group of fungi. It is found in hardwood forests of the southeastern United States, where it fruits in early spring soon after snowmelt.

<i>Verpa</i> Genus of fungi

Verpa is a genus of ascomycete fungi related to the morels. Resembling the latter genus in edibility and form, the common name early morels is popular. There are five species in the widespread genus.

<i>Morchella elata</i> Species of fungus

Morchella elata is a species of fungus in the family Morchellaceae. It is one of many related species commonly known as black morels, and until 2012 the name M. elata was broadly applied to black morels throughout the globe. Like most members of the genus, M. elata is a popular edible fungus and is sought by many mushroom hunters.

<i>Verpa conica</i> Species of fungus

Verpa conica, commonly known as the bell morel or the early morel, is a species of fungi in the family Morchellaceae. Sometimes mistaken for a true morel, this species is an “early morel” characterized by a cap resembling a thimble that is freely attached to the stem.

<i>Verpa bohemica</i> Species of fungus in the family Morchellaceae found in northern North America, Europe, and Asia

Verpa bohemica is a species of fungus in the family Morchellaceae. Commonly known as the early morel or the wrinkled thimble-cap. The mushroom has a pale yellow or brown thimble-shaped cap—2 to 4 cm in diameter by 2 to 5 cm long—that has a surface wrinkled and ribbed with brain-like convolutions. The cap hangs from the top of a lighter-colored, brittle stem that measures up to 12 cm long by 1 to 2.5 cm thick. Microscopically, the mushroom is distinguished by its large spores, typically 60–80 by 15–18 µm, and the presence of only two spores per ascus.

<i>Morchella rufobrunnea</i> Species of edible fungus in the family Morchellaceae

Morchella rufobrunnea, commonly known as the blushing morel, is a species of ascomycete fungus in the family Morchellaceae. A choice edible species, the fungus was described as new to science in 1998 by mycologists Gastón Guzmán and Fidel Tapia from collections made in Veracruz, Mexico. Its distribution was later revealed to be far more widespread after several DNA studies suggested that it is also present in the West Coast of the United States, Israel, Australia, Cyprus, Malta and Switzerland.

<i>Morchella tridentina</i> Species of fungus

Morchella tridentina is a cosmopolitan species of ascomycete fungus in the family Morchellaceae. Commonly referred to as the mountain blond or western blond morel in North America, it produces conical, grey to buff fruit bodies that are rufescent and grow up to 20 cm (7.9 in) tall and 5 cm (2.0 in) wide. This early-diverging species is distinct within the /Elata clade due to its pale colours and has been described by many names in the past, including M. frustrata, M. quercus-ilicis, M. elatoides, M. elatoides var. elegans and M. conica var. pseudoeximia, all of which were shown to be synonyms. A widely distributed relict of the last Ice Age, M. tridentina is so far known from Argentina, Armenia, Chile, Cyprus, France, India, Israel, North America, Spain and Turkey.

<i>Morchella importuna</i> Species of fungus

Morchella importuna is a species of fungus in the family Morchellaceae described from North America in 2012. It occurs in gardens, woodchip beds, and other urban settings of northern California and the Pacific Northwest region of the United States and Canada. The fungus has also been reported from Turkey, Spain, France, Switzerland, Canada and China, although it is unknown whether this is a result of accidental introductions. It is considered a choice edible mushroom. The fruit bodies develop a distinctive ladder-like pattern of pits and ridges on the surface of their conical caps.

<i>Morchella populiphila</i> Species of fungus

Morchella populiphila is a species of morel fungus native to northwestern North America. Described as new to science in 2012, its specific epithet refers to its association with black cottonwood. The morel used to be referred to as Morchella semilibera in western North American field guides until molecular analysis established that to be a strictly European species. M. populiphila occurs in California, Nevada and Oregon. Its fruit bodies grow up to 15 cm (6 in) tall with a ridged and pitted conical cap that attaches about halfway down the stipe. The cap ridges are dark brown to black in maturity, while the pits are yellowish to brownish. The fungus is edible, although not as highly valued as other morels.

References

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  2. Bresinsky A, Besl H. (1990). A colour atlas of poisonous fungi. Wolfe Publishing Ltd, London.
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  6. Evira: Gyrotoxin i stenmurklor Archived 2011-05-04 at the Wayback Machine
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