BRIEF DESCRIPTION: The following description is based on Beeli (1935).

The cap of Amanita annulatovaginata is 80 - 90 mm wide, ovoid then plano-convex, slightly umbonate, umbrinous brown to fuligineous, undecorated, with a striate margin. The flesh is white and thin.

The gills are free, pointed at both ends, 8 - 10 mm wide, and white.

Its stem is 180 - 190 × 7 - 8 mm, cylindric, stuffed, undecorated, bistre, and brownish-black. The ring is a superior, submembranous, white, and easily broken. The volva is saccate, membranous, ample, bistre or umber. The flesh is white.

The spores measure 8 - 10 × 6 - 8 µm and are broadly ellipsoid to ellipsoid and inamyloid. Spores from the type and similar paratype as drawn in Gilbert (1940) are as follows: 11.1 - 14.9 × 6.5 - 10.5 µm [9 spores] and are  ellipsoid to elongate.
Spores from the type of A. annulatovaginata var. atra: 9.9 - 11.1 × 6.6 - 7.8 µm [5 spores] and ellipsoid. Spores from var. citrina: 12.3 - 12.9 × 7.9 - 8.3 µm [2 spores] and ellipsoid to elongate. Spores identified only at the species rank but not the same size as those of the type: 10.3 - 11.9 × 6.0 - 7.7 µm [4 spores] and are ellipsoid to elongate.

The present species was originally described from the Republic of Congo in forest.

Beeli distinguished four varieties within this species. In addition to the type variety, he proposed A. annulatovaginata var. citrina Beeli differentiated only by a yellowish cap, A. annulatovaginata var.amethystina Beeli with a violacious cap, and A. annulatovaginata var. atra Beeli with a violet-black cap. Gilbert (1940) proposed that var. atra and var. amethystina were essentially identical with the type variety.

Madame Goossens' watercolors show the stipe completely distinguishable from the volval sac and the annulus more or less persistent at maturity. The degree of pigmentation of the stem appears variable in her paintings and is never as dark as the written description suggests. The reproduction of her painting in Gilbert (1941 tab. 11) is much too dark and has lost the subtly of coloring of the original.