Technical Description. (t.b.d.)

BRIEF DESCRIPTION: The description of Amanita marmorata is based on the original descriptions of the three synonyms above, which appear in the following works: Gilbert (1941), Eicker et al. (1993), and O. K. Miller et al. (1996).

The cap of Amanita marmorata is 30 - 72 (-95) mm wide, with a densely flecked (not quite virgate or streaked) surface having a mixture of small areas colored brown or gray or gray-brown, (sometimes slate gray or dark gray-brown in the center, sometimes with a yellowish tint in the center, sometimes with all pigmented flecks gray in age) and white or whitish, creating a marbled appearance, shallowly campanulate to shallowly convex to planar, with a nonstriate, nonappendiculate margin.  The universal veil is almost always absent.  If present, it forms a white, membranous patch.

The gills are crowded, free to narrowly attached, white to creamy white, and rather narrow.

The stem is 30 - 70 × 5 - 15 mm,  silky, white to dirty white, farinose above the ring, sometimes with zig-zag ("flame" or "zebroid") markings below the ring.  The ring is apical, skirt-like, white, and membranous.  The stem bears an ample,  weakly membranous, limbate volva arising from near the top of the stem's bulbous base (which is up to 22 mm wide).

The spores measure (6.8-) 7.5 - 10.0 (-11.8) × (5.8-) 6.2 - 8.0 (-9.5) µm, are subglobose to broadly ellipsoid to ellipsoid (rarely elongate) and are amyloid.  Clamps are not found at bases of the basidia.

Amanita marmorata is deadly POISONOUS.  The species contains amatoxins.

Amanita marmorata was originally described from the state of South Australia.  It has been exported with Australian plants to both South Africa and the Hawaiian Islands, USA.  In each of these localities it received a new name.  For similar taxa, see the page for A. phalloides (Fr.:Fr.) Link.  Plants reportedly associated with the present species in Hawaii include Eucalyptus, Casuarina, Araucaria, and Melaleuca (Miller et. al., 1996).  In South Africa, Eucalyptus is reported as the sole associated genus (Eicker et al., 1993)

The material that I have examined (for example, for spore measurements above) is largely from Hawaii.  The editors of these pages are both interested in obtaining well-documented, well-dried collections from Australia and South Africa as well as Hawaii. -- R. E. Tulloss

Photos: Jon Dale (Oahu, Hawaii, U.S.A.)

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Last changed 30 July 2005.
This page is maintained by R. E. Tulloss.
Copyright 2005 by Rodham E. Tulloss.
Photographs copyright 3005 by Jon Dale.