Tom Volk's Fungus of the Month for September 1997

This month's fungus is the death angel, Amanita bisporigera, Amanita virosa, and Amanita verna

For the rest of my pages on fungi, please click TomVolkFungi.net

You're missing a beautiful Amanita bisporigera picture Some of the most beautiful, but most deadly fungi are a group of species collectively known as the death angel. A single specimen of any of these three mushrooms, Amanita bisporigera, Amanita virosa, and Amanita verna, can be deadly. All three species are pure white, with white gills that are free from the stalk. All have an annulus, or ring (which is the remnant of the partial veil, which protects the gills as they are developing) around the stalk. All three have a volva, or cup at the base, which is the remnant of the universal veil that surrounded the young fruiting body primordium. Like all Amanita species, they are mycorrhizal, which means they have a symbiotic (mutualistic) association with the host tree. In our part of the country the association is with oak (Quercus spp.) trees, but in other parts of the country the association may be with other hardwoods or conifers.




Amanita virosa with KOHThese three species are difficult to distinguish from one another without the use of a microscope. Under the microscope, Amanita bisporigera can be distinguished by its two-spored basidia; macroscopically it tends to be more slender and delicate than the other two species. Amanita virosa and A. verna are difficult to distinguish from one another, but a drop of KOH on the cap of A. virosa turns it bright yellow, as in the accompanying photograph. I have never seen A. verna, so I don't have a picture of it.

The toxin in the death angel is a relatively small protein of eight amino acids, a cyclopeptide called alpha-amanitin (I'll be darned if I can find out how to code for the Greek letter alpha). According to John W. Rippon, Professor Emeritus at the University of Chicago in Medical Mycology, alpha-amanitin works by slowly attacking RNA polymerase, an enzyme in the liver. It ultimately affects the central nervous system and kidneys. Unlike many fungal toxins it does not cause symptoms right away. 6-24 hours after ingestion there may be an early feeling of unease, followed by violent cramps and diarrhea. On the third day, there is a remission of symptoms, but this is a false remission. On the 4th to 5th day the enzymes increase and liver and kidneys are severely affected. Death often follows if a liver transplant or other heroic measures are not performed. The same toxin is, coincidentally, found in a completely unrelated mushroom Galerina autumnalis.

According to some people who have eaten the death angels (and died), they have a rather good taste, so you can't trust your taste buds in picking poisonous from edible mushrooms. However, I do not recommend tasting it!!!!! If you plan on eating any mushroom you must be absolutely sure of the genus and species identification. A meal, no matter how delicious, is not worth the price of your life.


Amanita muscariaThere are a number of other Amanita species, most of which are quite beautiful, including Amanita muscaria, the fly agaric, to your left, as well as Amanita caesarea See this subdirectory of my images site for pictures of more species of Amanita

If you have anything to add, or if you have corrections or comments, please write to me at volk.thom@uwlax.edu

This page and other pages are © Copyright 1997 by Thomas J. Volk.

Return to Tom Volk's Fungi Home Page -- http://TomVolkFungi.net