Amanita phalloides

What You Should Know

Amanita phalloides, commonly known as the death cap mushroom, is one of the most poisonous mushrooms in the world. It is found in various parts of the world, including Europe, North America, and Asia. It contains amatoxins, which are a group of potent toxins that can cause severe liver damage, leading to organ failure and death if left untreated. The amatoxins are heat-stable, meaning they are not destroyed by cooking or drying.

The death cap mushroom has a cap that is usually greenish-yellow or yellowish-brown, with white gills underneath. It has a white stem that is surrounded by a cup-like structure at the base. It is found in various parts of the world, including Europe, North America, and Asia. It is commonly found growing under oak trees, but it can also be found growing under other trees.

The symptoms of Amanita phalloides poisoning typically do not appear until 6 to 24 hours after ingestion. The initial symptoms include abdominal pain, vomiting, and diarrhea. This is followed by a period of apparent recovery, but then the liver and other organs start to fail, leading to death if left untreated.

Amanita phalloides can produce circles of fruiting bodies, known as fairy rings, which over centuries have been the subject of fairy tales and folklore.

Other names: Death Cap, Stinking Amanita, Deadly Amanita, Czech Republic (Muchomůrka Zelená).

Amanita phalloides Mushroom Identification

1. Cap

   The cap is 4-16 cm in wide and starts off nearly round or oval, then becomes convex, and eventually becomes broadly convex to flat as it ages. It is bald and sticky when wet, but shiny when dry. The color ranges from dull green to olive to yellowish to brownish, although rare white forms can also be found. The cap is finely and innately streaked, occasionally with one or a few patches of white veil material. The margin is usually not lined.

2. Gills

   Free from the stem or nearly so; white (sometimes with a slight greenish tint); close or crowded.

3. Stem

   The stem is 5-18 cm long and 1-2.5 cm thick. It is either equal in width or tapers towards the top and flares out to a swollen base. The stem can be bald or have fine hairs, and it is white or has a similar color to the cap. There is a white ring around the stem that looks like a skirt, which usually remains but can sometimes disappear. The base of the stem is encased in a white, sack-like volva, which can sometimes be underground or broken up.

4. Flesh

   White throughout; unchanging when sliced.

5. Spores

   The spores measure (7.5-) 8.0 - 10.1 (-13.5) × (5.5-) 6.1 - 8.0 (-10.5) µm and are subglobose to broadly ellipsoid to ellipsoid and amyloid. Clamps are not found at bases of basidia.

6. Spore Print

   White.

7. Odor and Taste

   In age, the odor of this mushroom is distinctively repugnant and can be detected at a distance. It is various described as "sickeningly sweet," "like rotten honey," "like carrion," etc.

8. Habitat

   Solitary, scattered, to gregarious under coast liveoak (Quercus agrifolia), occasionally with other oaks and ornamental hardwoods; fruiting sporadically during the summer months in watered areas or from fog drip along the coast; common from early fall to mid-winter.

Amanita phalloides Look-Alikes

1. Agaricus campestris

   Do not have volvae. The gills of immature mushroom is not gray or pinky-brown indeed to young young Agaricus mushrooms.

2. Amanita citrina

   Smells strongly of raw potatoes and has brownish-cream veil fragments on the cap.

Amanita phalloides Toxicity and Treatment

Amanita phalloides is a poisonous mushroom that contains three main toxins: amatoxins, phallotoxins, and virotoxins. The primary toxin responsible for the toxic effects on the human body is α-amanita, which inhibits RNA polymerase II, leading to a lack of protein and eventual cell death. However, other mechanisms may also be involved.

The liver is the primary target organ for toxicity, but other organs, especially the kidneys, may also be affected. Symptoms of poisoning typically appear after an incubation period and may include gastrointestinal distress, jaundice, seizures, and coma, eventually leading to death.

Treatment involves supportive measures, gastric cleansing, medication, and potentially liver transplantation if the condition worsens.

Symptoms:

1. Gastric-intestinal troubles (nausea, alimentary vomiting, then biliary, watery diarrhea), dehydration with consequent hypotension, strong thirst, abdominal pains.

2. Apparent improvement.

3. Acute hepatic insufficiency and appearance of icterus, coagulopathy, at times serious dehydration with acute renal insufficiency, lethargy, coma, and possible death. In any case, as a consequence of the acute hepatic insufficiency, the liver might be irreversibly jeopardized, to the point to necessitate transplantation.

Unfortunately, there is currently no effective antidote for Amanita phalloides poisoning, and finding one remains a significant challenge. Research efforts will continue to identify potential antidotes and improve therapy for these mushrooms.

Amanita phalloides Taxonomy and Etymology

The species was first described by French botanist Sébastien Vaillant in 1727, who gave it the concise name "Fungus phalloides, annulatus, sordide virescens, et patulus" which is still used today. In 1821, Elias Magnus Fries included all white amanitas in his description of Agaricus phalloides. However, in 1833, Johann Heinrich Friedrich Link settled on the name Amanita phalloides, despite Persoon having previously named it Amanita viridis 30 years earlier. Some taxonomists have disputed the rejection of Louis Secretan's use of the name A. phalloides, as it predates Link's naming, but it is not recognized for nomenclatural purposes due to inconsistent use of binomial nomenclature in Secretan's works.

The name phalloides, which means "phallus-shaped", was given to the species because of its resemblance to either a literal phallus or the stinkhorn mushrooms known as Phallus.

Amanita phalloides Synonyms

1. Venenarius phalloides ( Fr.) Murrill, 1912

2. Amanitina phalloides (Fr.) E.-J. Gilbert, 1940

3. Fungus phalloides Vaill.

4. Agaricus phalloides Vaill. ex Fr.

5. Amanita viridis Pers.

6. Amanita phalloides Secr. (nomen nudum) nud.

Sources:

Photo 1 - Author: Daniel Neal from Sacramento, CA, US (Creative Commons Attribution 2.0 Generic)

Photo 2 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 3 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 4 - Author: Michel Langeveld (Creative Commons Attribution-Share Alike 4.0 International)

Photo 5 - Author: misspril (Creative Commons Attribution-Share Alike 4.0 International)