BRIEF DESCRIPTION: This description is based on Dr. Bas' thesis on section Lepidella (1969).

The cap of A.crassa is about 150 mm wide, convex with a slightly depressed center, thick-fleshed, white, dry, strongly appendiculate, with a nonstriate, slightly inflected margin.  The cap is covered with thick, adnate, radially fibrillose, polygonate patches to truncate pyramidal warts with felted tips, towards the margin these warts gradually pass into thick, shingle-like, fibrillose scales with felted, subtruncate tips.

The gills are crowded, free, rather thick, moderately broad, and pale buff.  The short gills are attenuate.

The stem is about 100 x 50 mm, white, subfelted to glabrous, annulate, with two thick, concentric, subfloccose volval rims on the upper half of the bulbous part.

The spores measure (6.5-) 7 - 9 x 4.5 - 6 µm and are amyloid and ellipsoid to elongate.  Clamps are abundant at bases of basidia.

Amanita crassa is known only from Argentina, the type was found in dung, although that doesn't resolve the issue of whether the species forms mycorrhizae.