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Ring (veil)

Movable ring

Movable ring — mushrooms with the trait «Movable ring»

Most mushroom rings are firmly attached to the stem. But nature has created one unique mechanism: a ring that doesn't fuse with the stem tissue at all and can slide freely up and down it, like a ring on a finger. In mycology this is called a movable ring.

0 species in the database.

No mushrooms with this trait yet.

How does a movable ring form?

In the "Key to the Fungi of Ukraine," M.Ya. Zerova explains that such a ring forms in mushrooms with a very complex veil anatomy. As the cap opens, the dense, thick membrane tears away from the cap margin, but its inner edge doesn't grip the smooth surface of the stem firmly. Once it dries, the ring becomes a free-standing "bracelet" that hangs loosely on the stem.

The emblem of parasol mushrooms

David Arora and Roger Phillips note that a movable ring is an absolute diagnostic feature of one of the tastiest woodland mushrooms — the genus Macrolepiota, in particular the parasol mushroom (Macrolepiota procera).

The parasol mushroom is a giant with a tall stem (up to 30 cm) and a big scaly cap. Its ring is huge, thick, double-layered and has fluffy edges. If you find a mature parasol mushroom, you can take this ring between two fingers and easily slide it up and down the stem. It's the best and simplest safety test for this mushroom!

Other parasols have a movable ring as well (for example, the shaggy parasol — Chlorophyllum rhacodes).

Dangerous lookalikes without a movable ring

Knowing about the movable ring saves lives, because it lets you tell the edible big parasol from dangerous amanitas and small poisonous Lepiota:

- Panther cap and death cap: Their rings are firmly attached to the stem (hanging like a skirt). If you try to slide such a ring, it will simply tear.

- Poisonous Lepiota (Lepiota): These small relatives of the parasols, which contain deadly amatoxins, usually have thin, attached rings that quickly fall apart and don't slide along the stem. (That's why there's a rule: don't pick "parasols" with a cap smaller than 10 cm.)

Questions and answers

Why does a parasol's movable ring sometimes not move?
In very young parasols (when the cap hasn't opened yet and looks like a "drumstick"), the ring is still firmly joined to the cap margin. It only becomes movable once the parasol has fully opened. Also, after heavy rain a wet ring can stick to the stem; to get it sliding, gently lift it with a fingernail.
Can you eat the ring of a parasol mushroom itself?
Yes, the ring of the parasol mushroom is edible and has the same pleasant nutty flavor as the cap. The parasol's stem itself (the one the ring slides along), however, is usually thrown away or dried and ground into powder, since it's too tough and woody.
Are there Agaricus with a movable ring?
No. The rings of all woodland and store-bought Agaricus are firmly attached to the stem and don't slide. A movable ring is an exclusive trick of the big parasols.

Sources

  1. 1.Зерова М.Я. та ін. Визначник грибів України. 1979
  2. 2.Roger Phillips. Mushrooms (Roger Phillips)
  3. 3.David Arora. Mushrooms Demystified
  4. 4.Index Fungorum