A. virosa first appears as a white egg-shaped object covered with a universal veil. As it grows, the mushroom breaks free, though there may be ragged patches of veil at the cap edges. The cap is initially conical with inturned edges, before becoming hemispherical and flattening with a diameter up to 12 cm (4½in). The cap often has a distinctive boss; it is able to be peeled and white, though the centre may be ivory in colour. The crowded free gills are white, as is the stipe and volva. The thin stipe is up to 15 cm (6 in) tall, with a hanging grooved ring. The spore print is white and the spores egg-shaped conical and 7–10 μm long. They stain blue with iodine. The flesh is white, with a taste reminiscent of radishes, and turns bright yellow with sodium hydroxide.
This fungus highlights the danger of picking immature fungi as it resembles the edible mushrooms Agaricus arvensis and A. campestris, and the puffballs (Lycoperdon spp. ) before the caps have opened and the gills have become visible.
The ability to be peeled has been taken as a sign of edibility in mushrooming, which is a potentially lethal mistake in this species. It is unclear why this fungus which more closely resembles edible species has been implicated in fewer deaths than the death cap, though its rarity may contribute to this.
Distribution and habitatEdit
A. virosa is found in mixed woodland, especially in association with beech, on mossy ground in summer and autumn. All Amanita species form ectomycorrhizal relationships with the roots of certain trees.