Deoxynivalenol (DON) is a toxin found in grains infected with the fungus Fusarium graminearum and other Fusarium species. It is often called “vomitoxin” because it primarily causes vomiting in humans and livestock. Its long-term effects are mild, but it is still a very important mycotoxin because it is the most common mycotoxin found in food.
fungi in the phylum Ascomycota
Fungi produce innumerable “mycotoxins” – compounds that are toxic to humans. In mushrooms, these cause symptoms ranging from gastrointestinal upset to death (see FFF#091–100 for more). Although these are of significant concern to mushroom hunters, their impact is relatively small. The most significant mycotoxins in terms of the number of people affected are produced by molds that naturally grow on food. Over the next few weeks, I will discuss some of the most problematic food-borne mycotoxins. Topping that list are the aflatoxins, which cause liver cancer and are especially problematic for people in developing nations.
In late October, it is not unusual to see Halloween decorations featuring bony fingers reaching up out of a grave. The natural world has its own version of this: Xylaria polymorpha, commonly known as Dead Man’s Fingers. This macabre name is an apt description of the mushrooms, which resemble burnt and dried out fingers reaching out of the ground to grab unwitting passers-by and drag them down into the depths of the earth. You can find these morbid ascomycetes on rotting logs at pretty much any time of the year.
Tolypocladium ophioglossoides (also called Cordyceps ophioglossoides and Elaphocordyceps ophioglossoides) is a fun little mushroom to find, but you have to be paying attention to enjoy it. Unlike most fungi that were placed in Cordyceps, which were insect parasites, T. ophioglossoides – commonly known as the “Golden Thread Cordyceps” (even though it is no longer in that genus) – attacks other fungi. Specifically, it parasitizes truffles in the genus Elaphomyces. If you can spot this tiny brown/black mushroom, make sure to dig it up carefully and follow the golden thread that attaches the mushroom to its truffle host.
Warfarin is one of the most successful drugs of all time. Seventy years after it was first synthesized, warfarin is still the most widely prescribed anticoagulant. Warfarin has a unique story. What began as depression-era research into a mysterious disease of cattle ended up producing two life-saving medicines and a rat poison that are still in use today.
Spathulariopsis velutipes is an odd little mushroom that looks like a spatula or a canoe paddle, though perhaps in a half-melted kind of way. Its common names include “velvety fairy fan,” “velvet foot Spathularia,” and variations on those. This ascomycete is an earth tongue look-alike (ETLA)* that is easily differentiated from similar mushrooms thanks to its unique shape and the strikingly different colors and textures of its head and stipe. I always enjoy finding this mushroom because of its unique appearance.
Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of what we’ve learned about fungi from May through early July 2017. Read below to learn about: early fungal fossils, fungal epigenetics, the best way to cook mushrooms, liver disease, malaria, and more! Visit the associated links to get the full story.
For some reason, the strange little mushrooms produced by the ascomycete Leotia lubrica are called “Jelly Babies” (or “Jellybabies”). They do look a little like the mushroom version of gummy fruit snacks, but that’s as close as I can get to understanding their common name. When fresh, these small yellow and brown mushrooms have a smooth but wrinkled and slimy cap held aloft by a gently curving stalk, so they do look somewhat like a gelatinous morsel on a stick.
Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of what we’ve learned about fungi from March through April 2017. Read below to learn about: C. auris in the U.S., aflatoxin-destroying corn, viruses defying fungal incompatibility, fungus-farming ant evolution, bat and salamander diseases, and more! Visit the associated links to get the full story.
Reindeer Lichens grow in northern temperate forests, boreal forests, and even in the tundra. They are highly branched, fruticose lichens that are a primary food source for reindeer (also called caribou in North America). These lichens are sometimes called “Reindeer Moss,” even though they are lichens and not moss.