Amanita bresadolana

The following is based on the description in Neville and Poumarat (2004).  Neville and Poumarat's description is based largely on the original description by Bresadola (1881).

The cap of A. bresadolana is 20 - 30 mm wide [Note: apparently measured edge to edge of a bottom of an incompletely opened cap], not very fleshy, campanulate-conic, dry, smooth, gray or slightly ash-gray, with a short-striate margin.  The flesh is thin.

The gills are free or touching the stem, narrow towards both ends, crowded, white , with a finely decorated and uneven edge.  The short gills are "subrounded" (?subtruncate).

The stem is 40 - 50 × 4 - 5 mm, stuffed to partially hollow, cylindric, nearly smooth, and grayish.  The ring is subapical, proportionately large, membranous, persistent, white, nonstriate, with yellowish floccose scales on the bottom side.  The saccate volva is whitish, rather thick (for an Amanita), attached at the bottom of the stem, substantially thickened below the stem (from Bresadola''s original illustration), with the upper part separated into lobes.  The flesh is white to pale gray.

No odor is present.

The spores measure 10 - 12 × 8 µm and are broadly ellipsoid to ellipsoid and inamyloid.  Presence or absence of clamps on bases of basidia is unknown, but probably present.

This species was originally described from broad-leaved forests in Italy (Val di Sole).

In the illustration of Bresadola the gills are not shown white as is the flesh of the cap, the ring, the volva, and the cross section of the volva but are shown concolorous with the cross section of the stem which, given the description, suggests that they are grayish, or given the color in the illustration, suggests that they are yellowish-cream.  When Bresadola republished the plate in 1927 the gills are shown as white.  If the illustration accurately represents the shape of the short gills, they are rounded-attenuate and not truncate.  The 1927 illustration also shows a more robust fruiting body, the origin of which is not known.

No dried material of Amanita bresadolana is known to exist.  Due to the colors and the ellipsoid spores, this species has for some reason been thought to be a synonym of A. spreta (Peck) Sacc., a robust, rather common, eastern North American species. Amanita spreta has a cellular subhymenium and will probably be placed in Amanita stirps Hemibapha or Amanita stirps Caesarea when the species is revised.  Since the subhymenium of A. bresadolana is unknown, its placement cannot be made with certainty.  Among the differences with A. spreta are that the latter has a ring that becomes gray and is proportionately small and placed lower on the stem, a volval sac which is often left only in rather small part at the base of the stem and is attached at the side as well as the bottom of the stem, a cap not at all conic at first, short gills that are truncate to rounded truncate to subtruncate, 95th percentile of spore width is less than 8 µm, and the average spore is elongate.

Now that Neville and Poumarat have provided a valid name for this entity, we hope that this will motivate a renewed search for material satisfying the type description.  Until that happens and such material is revised, this species will remain poorly known and little understood.—R. E. Tulloss and L. Possiel

The editors of this site owe a great debt to Dr. Cornelis Bas whose famous cigar box files of Amanita nomenclatural information gathered over three or more decades were made available to RET for computerization and make up the lion's share of the nomenclatural information presented on this site.