Poisonous Mushrooms: How Many Species Exist?

There are over 14,000 species of mushrooms worldwide, but there is no standard identifier for poisonous mushrooms. While only 15-20 species are potentially lethal when ingested, many more can cause serious health issues. Poisonous mushrooms contain a variety of different toxins, including amatoxins, which can cause vomiting, diarrhoea, liver damage, and even organ failure. The toxicity of mushrooms has evolved independently, and researchers have found that different mushroom species can share the same types of toxins. The shape, colour, and smell of a mushroom's cap are not reliable indicators of its toxicity. To prevent mushroom poisoning, foragers should familiarize themselves with both edible mushrooms and similar-looking toxic species.

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There are over 14,000 species of mushrooms worldwide, but no standard identifier for poisonous ones

Unfortunately, there is no easy way to identify poisonous mushrooms. Old wives' tales suggest that poisonous mushrooms are brightly coloured, or that insects and animals will avoid them. However, these beliefs are unreliable. For example, the deadly destroying angel mushroom is unremarkably white, while the poisonous galerinas are brown. Conversely, some edible mushrooms, like chanterelles, are brightly coloured. Similarly, while insects and animals may avoid certain toxic mushrooms, some fungi that are harmless to invertebrates can still be poisonous to humans.

The shape of the mushroom cap is also not a reliable indicator of toxicity. The death cap, for instance, has a rounded cap when mature, similar to many edible mushrooms. Boletus mushrooms are generally safe to eat, but the Devil's bolete is an exception, as it is poisonous both raw and cooked. Other boletus mushrooms, like the lurid bolete, require thorough cooking to break down toxins.

To prevent mushroom poisoning, it is essential to correctly identify mushrooms before consuming or foraging them. Cross-referencing with multiple sources or seeking assistance from professionals is recommended. Additionally, it is crucial to obtain proper permissions before foraging in specific areas. Avoiding mushrooms with certain characteristics, such as white gills, a skirt or ring on the stem, a bulbous base, or red on the top of the stem, can also reduce the risk of encountering poisonous varieties.

It is worth noting that some mushrooms contain toxins that are heat-stable, meaning they cannot be rendered safe to eat by cooking. Amatoxins, for example, are extremely toxic compounds found in mushrooms like death caps and destroying angels, and they do not break down during cooking. Therefore, it is crucial to positively identify mushrooms before consuming or cooking them, as ingesting certain toxic varieties can lead to severe gastrointestinal distress, organ failure, and even death.

Poisonous mushrooms contain a variety of toxins, with symptoms ranging from vomiting to organ failure

There are about 100 species of mushrooms that are toxic out of the vast number of mushroom species in existence. Poisonous mushrooms contain a variety of toxins, with symptoms ranging from vomiting to organ failure. The symptoms of mushroom poisoning depend on the toxin ingested and may range from dehydration in benign cases to renal failure, liver failure, and death in severe cases.

The most common consequence of mushroom poisoning is gastrointestinal upset, including nausea, vomiting, abdominal pain, and diarrhoea. However, some toxins can cause more serious symptoms such as liver and kidney damage, which can be fatal. Serious symptoms do not always occur immediately after eating and may not appear until days or weeks later, when the toxin has attacked the kidney or liver.

Some of the deadliest species of mushrooms include Amanita, Galerina, and Lepiota, which share the same type of amatoxin called amanitin. Amatoxin poisoning can cause altered sensorium and euphoria, abdominal cramping, nausea, vomiting, and diarrhoea. Other toxins found in mushrooms include orellanine, which causes kidney failure, and muscarine, which stimulates the nerves and muscles, causing sweating, salivation, tears, blurred vision, palpitations, and respiratory failure in high doses.

It is important to note that there is no reliable way to visually identify poisonous mushrooms. While some old wives' tales suggest that poisonous mushrooms are brightly coloured, this is not always the case. The shape of the mushroom cap also does not indicate the presence or absence of toxins. Therefore, it is crucial to familiarize oneself with the local edible and toxic mushroom species before consuming any wild mushrooms.

Death Caps are responsible for most fatal mushroom poisonings, often due to their resemblance to edible species

There are 70 to 80 species of poisonous mushrooms, but only a few of these are fatal when ingested. The death cap (Amanita phalloides) is perhaps the deadliest mushroom in the world. It is responsible for about 90% of mushroom-related fatalities worldwide.

Death caps are often mistaken for edible mushrooms, which is why they are responsible for most fatal mushroom poisonings. The white form of Amanita phalloides, for example, may be confused for edible Agaricus species, while juvenile death caps can resemble edible puffballs. Death caps also look similar to Caesar's mushroom and straw mushrooms, which are commonly consumed by humans.

The death cap mushroom contains amatoxins, which are highly toxic to the liver and other organs. Amatoxins are thermostable, meaning they are resistant to changes due to heat and cold, so cooking death caps does not reduce their toxic effects. Within 6 to 24 hours of consumption, victims experience violent abdominal pain, vomiting, and bloody diarrhoea, leading to a rapid loss of fluids and intense thirst. Eventually, the liver, kidneys, and central nervous system are affected, with symptoms including lowered blood sugar and decreased urinary output. Without quick, professional treatment, death caps can result in liver failure, kidney failure, encephalopathy, and death.

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Destroying Angels are several species of all-white mushrooms that are very toxic and similar to edible button mushrooms

While there are around 70-80 species of poisonous mushrooms, only a few of these are fatal when ingested. The Destroying Angel is one such species. It is, in fact, several species of all-white mushrooms that are very toxic and similar in appearance to edible button mushrooms. They are also similar to meadow mushrooms and horse mushrooms.

The scientific name for the Destroying Angel is Amanita virosa, and it is found in Europe. In North America, there are three similar species: Amanita bisporigera in the east, Amanita ocreata in the west, and Amanita amerivirosa in the north. These mushrooms are characterised by their gills and white stalks. The cap can be pure white, or white at the edges with a yellowish, pinkish, or tan centre. Destroying Angels can be found in woodlands, lawns, or grassy meadows near trees or shrubs. They are often found near oak, beech, chestnut, pine, spruce, and fir trees.

The Destroying Angel is one of the most toxic known mushrooms, containing the poison amatoxin, which causes liver failure. Symptoms of Destroying Angel poisoning include severe vomiting, diarrhoea, and abdominal pains, followed by a few days of apparent recovery, and then death from kidney and liver failure. Amatoxin poisoning is treatable if medical care is sought quickly. Excessive hydration can be very helpful immediately after ingestion, and in hospitals, an extract of milk thistle may be used to treat the poisoning. If not, dialysis followed by a liver transplant may be necessary.

To prevent mushroom poisoning, it is important to be able to recognise toxic species. The Destroying Angel, for example, has a skirt on the stem and remains of the volva or egg sack it grew from. It is also important to know which mushrooms are edible. For instance, it is recommended to slice puffball-like mushrooms in half when collecting them, as young destroying angels enclosed in their universal veils can be mistaken for puffballs.

Autumn Skullcaps are poisonous and can be deadly, sometimes mistaken for hallucinogenic mushrooms

There are 70-80 species of poisonous mushrooms, and many of these deadly fungi bear an unfortunate resemblance to edible mushrooms. This makes them especially dangerous, and it is important to be able to distinguish between the two. Autumn Skullcaps, for example, are poisonous and can be deadly, sometimes mistaken for hallucinogenic mushrooms.

Autumn Skullcaps, or Galerina marginata, are gilled, wood-rotting mushrooms that contain the same amatoxins as the death cap mushroom. Amatoxins are heat-stable peptides that cannot be destroyed through cooking. Ingestion causes vomiting, diarrhoea, hypothermia, and liver damage, and can result in death if left untreated. The caps of these mushrooms are light honey-brown to cinnamon-brown, and the hue changes as the mushroom matures. The caps are typically slightly slimy to sticky when wet but otherwise tacky when dry. The size of the cap varies from 0.5 inches when young to 3.25 inches across at maturity. The shape of the cap starts out slightly bell to convex-shaped when young and expands to broadly convex to flat when mature. The gills are attached to the stipe and are a honey-brown colour, turning to a darker rust-brown as the spores mature. When young, the gills are covered by an off-white partial veil. The stipe is typically off-white on the upper portion, becoming light brown towards the base.

Autumn Skullcaps are also known as Deadly Skullcaps, and they can be easily confused with the edible honey mushroom. The honey mushroom, or Armillaria mellea, is a delicious edible that appears in large clusters. However, it is important to be able to distinguish between the two, as Autumn Skullcaps are highly toxic.

To prevent mushroom poisoning, it is crucial to familiarize yourself with the mushrooms you intend to collect and be aware of any similar-looking toxic species. While it may be tempting to go mushroom foraging, it is always best to practice your foraging journey under the guidance of a mushroom expert.

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