Amanita porphyria

Description

Amanita porphyria can be found in our conifer forests during the latter part of summer and into fall. It is medium-sized with a gray to gray-brown cap with violet or reddish-gray tones. Usually, there are small, grayish warts or patches of veil tissue on the cap surface and around the margin of the distinctly bulbous stipe base.

The range of cap color for the species in North America is as broad as has been reported from Europe. Occasionally, specimens are found which are strongly virgate with pigments ranging from grayish-yellow to brown, sometimes having an apparent olivaceous tint.

This mushroom might contain dangerous toxins, as several other species from this genus do. This species should not be gathered for eating.

Common names: Booted Amanita, Gray-Veil Amanita, Grey Veiled Amanita, Purple Brown Amanita, Purplish Amanita, Porphyry Amanita.

Mushroom Identification

1. Cap

   40 - 80 mm wide, dull red to grayish dull red to graying purple or pale brown-gray to violaceous brown to violaceous gray-brown, darkest in the center, hemispherical then convex, with or without a broad umbo, finally planar, viscid, shiny, with the distinct appearance of having innate radial fibers, and with a nonstriate and non-appendiculate margin.

2. Gills

   The gills are free, rather crowded, whitish to pale yellowish gray, 4.5 - 8 mm broad, with a finely flocculose edge. The short gills are attenuate.

3. Stem

   60 - 110 × 6 - 14 mm, cylindric or slightly narrowing upwards, white or whitish, with fine striations above the ring, with violaceous gray or violaceous brownish longitudinal fibers present below the ring, solid and firm at first, giving the impression of the center being stuffed with cotton after some maturing, slowly becoming hollow.

4. Bulb

   The bulb is subglobose, marginate, and 12 - 36 mm wide. The ring is membranous, thin, skirt-like, finally collapsing on the stem, whitish or pale gray at first, rapidly becoming violaceous gray overall and violaceous brownish near the edge.

5. Volva

   The volva is present as rather large violaceous gray-brown to violaceous gray plaques. The volva is present as more or less irregular plaques on the lower stem or bulb, friable, at first whitish or pale gray, rapidly becoming brownish lilac-gray particularly in detached fragments, with a short cottony white free limb on the bulb's upper margin; the limb maybe 1 - 6 mm high (rarely higher).

6. Flesh

   The flesh is whitish or pale cream, except fora narrow violaceous gray-brown region just under the cap skin.

7. Odor and Taste

   The odor is of radishes or newly dug potatoes. The taste is not recorded.

8. Spores

   Spores measure 7.5 - 9.5 × 7 - 9 µm and are globose to subglobose and amyloid. Clamps are absent at the bases of basidia. Spores measured by RET from European and U.S. collections are as follows: (7.5-) 8.0 - 9.8 (-11.2) × (7.0-) 7.5 - 9.2 (-11.0) µm and are globose to subglobose, infrequently broadly ellipsoid.

9. Spore Print

   White.

10. Season

    June to October.

Look-Alikes

1. Amanita citrina

   The cap color is different and the ring has a gray/violet coloration.

2. Amanita pantherina

   Has a white velar remains on the cap.

3. Amanita rubescens

   The flesh turns pink when it is cut.

4. Amanita excelsa

   The spores are bigger and gills are more densely crowded. Also, its stem ring more robust.

History

This fungus was described in 1805 under the current name, Amanita porphyria, by Johannes Baptista von Albertini and Lewis David de Schweinitz in their work Conspectus Fungorum in Lusatiae superioris agro Niskiensi crescentium e methodo Persooniana.

The name was then sanctioned by Fries, meaning that the name Amanita porphyria is given priority even if the normal nomenclatural rules would give precedence to another name – and indeed the Danish mycologist Heinrich Christian Friedrich Schumacher had already described the same species as Agaricus gracilis in 1803.

The epithet porphyria comes from the Ancient Greek word porphúra (πορφύρα), meaning the Tyrian purple dye.

Synonyms

1. Amanita tomentella Krombh., 1836

2. Agaricus porphyrius (Alb. & Schwein.) Fr. 1821

3. Amanita recutita (Fr.) Gillet, Hyménomycètes (Alençon): 42 (1874)

4. Amanitina porphyria (Alb. & Schwein.) E.-J. Gilbert, 1940

5. Agaricus porphyreus (Alb. & Schwein.) Fr., Syst. mycol. (Lundae) 1: 14 (1821)

6. Agaricus recutitus Fr., Epicr. syst. mycol. (Uppsala): 6 (1838)

Photo sources:

Photo 1 - Author: Nina Filippova (CC BY-SA 4.0)

Photo 2 - Author: mycowalt (CC BY-SA 4.0)

Photo 3 - Author: Svencapoeira (CC BY-SA 4.0)

Photo 4 - Author: Nina Filippova (CC BY-SA 4.0)