False morel

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
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, most often Gyromitra. Verpa species by contrast are in the Morchellaceae and are true morels.

Compared to morels[edit]

Gyromitra esculenta, a false morel

When gathering morels for the table, care must be taken to distinguish them from the poisonous "false morels", a term loosely applied to describe Gyromitra esculenta, Verpa bohemica, and other morel lookalikes. Although false morels are sometimes eaten without ill effect, they 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. False morels contain gyromitrin, an organic carcinogenic poison, 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 eat false morels 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 false morels from true morels are as follows:

  • Gyromitra species often have a "wrinkled" or "cerebral" (brain-like) appearance to the cap due to multiple wrinkles and folds, rather than the honeycomb appearance of true morels due to ridges and pits.
  • Gyromitra esculenta has a cap that is usually reddish-brown in colour, but sometimes also chestnut, purplish-brown, or dark brown.
  • Gyromitra species are typically chambered in longitudinal section, while Verpa species contain a cottony substance inside their stem, in contrast to true morels which are always hollow.
  • The caps of Verpa species (V. bohemica, V. conica and others) are attached to the stem only at the apex (top of the cap), unlike true morels which have caps that are attached to the stem at, or near the base of the cap. The easiest way to distinguish Verpa species from Morchella species is to slice them longitudinally.[9][10]

See also[edit]

References[edit]

  1. ^ Michelot D, Toth B (1991). "Poisoning by Gyromitra esculenta—a review". Journal of Applied Toxicology. 11 (4): 235–243. doi:10.1002/jat.2550110403. PMID 1939997.
  2. ^ Bresinsky A, Besl H. (1990). A colour atlas of poisonous fungi. Wolfe Publishing Ltd, London.
  3. ^ Karlson-Stiber C, Persson H (2003). "Cytotoxic fungi—an overview". Toxicon. 42 (4): 339–349. doi:10.1016/S0041-0101(03)00238-1. PMID 14505933.
  4. ^ Lampe KF. (1979). "Toxic fungi". Annual Review of Pharmacology and Toxicology. 19 (1): 85–104. doi:10.1146/annurev.pa.19.040179.000505. PMID 378111.
  5. ^ Christer Andersson: Stenmurklan – olämplig att äta. Toxikologiska enheten, Livsmedelsverket.
  6. ^ Evira: Gyrotoxin i stenmurklor Archived 2011-05-04 at the Wayback Machine
  7. ^ Michael W. Beug, Marilyn Shaw, and Kenneth W. Cochran. Thirty plus Years of Mushroom Poisoning: Summary of the Approximately 2,000 Reports in the NAMA Case Registry. From summary at "Archived copy". Archived from the original on 2011-07-20. Retrieved 2011-04-12.CS1 maint: archived copy as title (link)
  8. ^ Benjamin, Denis R. (1995). Mushrooms: poisons and panaceas — a handbook for naturalists, mycologists and physicians. New York: WH Freeman and Company. ISBN 0-7167-2600-9.
  9. ^ Kuo M. (2007). 100 Edible Mushrooms. Ann Arbor, Michigan: The University of Michigan Press. pp. 55–58. ISBN 978-0-472-03126-9.
  10. ^ Kuo M. (2005). Morels. Ann Arbor, Michigan: University of Michigan Press. p. 173. ISBN 978-0-472-03036-1.