BRIEF DESCRIPTION: The cap of Amanita calyptratoides is 30 - 100 mm wide, pale brownish-gray to pale brown to brown; it lacks an umbo, usually has marginal striations with length 10% to 20% of the cap radius (in large specimens striations may appear only with aging), and often bears one or more white membranous patches of the volva and/or a white "bloom" or "frost" over the disk.

The gills are free, close to subcrowded, white to pale cream in mass, and 4.5 - 8 mm broad; the short gills are more or less truncate, of varying length, unevenly distributed, and plentiful.

The stem is 50 - 145 x 6 - 20 mm, the color and appearance of a tallow candle; it bears a small white annulus that appears to dissolve into the stipe as time passes. There is a white, membranous, sack-like volva (20 - 45 x 15 - 45 mm) at the base.

The spores measure (8.5-) 9.8 - 14.0 (-17.0) x (5.5-) 6.5 - 8.9 (-11.8) µm and are ellipsoid to elongate (infrequently broadly ellipsoid) and inamyloid. Clamps are present at bases of basidia.

Amanita calyptratoides occurs with coastal live oak in central and southern California, U.S.A. and in the Baja California peninsula, Mexico.  Also, the present species has been found in oak-pine-fir forests of the neovolcanic zone of central Mexico.

The name is often misapplied. It has been mistakenly considered to be a synonym of A. calyptroderma G. F. Atk.  Amanita calyptratoides is very similar to A. calyptroderma microscopically, but can be differentiated from A. calyptroderma by spore size and shape and by the unusual stipe and "dissolving" annulus of A. calyptratoides.-- R. E. Tulloss