False Caesar's Mushroom

Amanita parcivolvata

''Amanita parcivolvata'' is a fungus that produces fruit bodies that vaguely resemble those of ''Amanita muscaria''. It is differentiated, however, by its lack of an annulus, by the volval deposits on its stipe/base, and by its pileal striations.
Amanita parcivolvata Growing at a disturbed forest edge, on a chert driveway. Gordon County, GA, US. September 2, 2020. 
https://www.jungledragon.com/image/100774/amanita_parcivolvata.html
https://www.jungledragon.com/image/100773/amanita_parcivolvata.html
https://www.jungledragon.com/image/100771/amanita_parcivolvata.html Amanita parcivolvata,False Caesar's Mushroom,Geotagged,Summer,United States

Appearance

It occasionally lacks a stipe bulb entirely, instead just tapering to a point in the ground with powdery volval deposits on its surface. It ranges from 3–12 cm in length and is occasional to common in the Southeastern United States, occurring primarily in ''Quercus'' forests though it has been observed in forests with a mix of conifers and oaks.

Cap: The pileus is bright red ranging from 3–12 cm in diameter with warts which range in color from pale yellow to white. With rain, these can wash off, giving it a somewhat similar appearance to an ''Amanita'' in ''section Caesareae'' from a distance, especially if all but the cap is covered by detritus.

Gills: The lamellae are white to pale yellow, closely spaced, free from the stipe, and sometimes with a serrated margin.

Stipe: 3–12 cm in length and about 1.5 cm in width, with pale yellow to white powdery volval remnants all along the stipe. The volva, if it even may be called that, is rather undeveloped as compared to other members of ''Amanita''.

Microscopic Features: According to Rod Tulloss, the spores of ''Amanita parcivolvata'' measure 9.1-11.5 X 6.3-7.9 μm, are inamyloid, and the basidia rarely have clamps at bases.

Chemical Reactions: With KOH, the red color of the cap quickly fades to an orange, then yellow color.

References:

Some text fragments are auto parsed from Wikipedia.

Taxonomy
KingdomFungi
DivisionBasidiomycota
ClassAgaricomycetes
OrderAgaricales
FamilyAmanitaceae
GenusAmanita
SpeciesA. parcivolvata