Genus Amanita, Section Validae, Subsection Mappae
Amanita aestivalis, A. brunnescens, A. citrina, A. porphyria, A. solaniolens
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Amanita porphyria
Photo by Pam Kaminski
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The cleft bulb of Amanita aestivalis
Photo by Eric Smith
They also have a skirt-like ring, and a smell like potatoes. Usually you can smell this best by sniffing the gills, or scratching and sniffing the bulb.
There are two different taxa that are tinged with purple or lilac. These are all eastern species, inhabitants of the great Appalachian forest remnant, except for Amanita porphyria, which is found all over.
Amanita aestivalis
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Amanita aestivalis: the all-white Amanita with a cleft bulb
Photo by Eric Smith
Perhaps more importantly, you would tell it from a destroying angel by the brown bruising (visible on the bulb of some of these) and the cleft bulb at the base of the stem.
Amanita brunnescens
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Amanita brunnescens
Photo by Eric Smith
Classic brunnescens has either a deep brown cap, or a very pale yellow cap. It can shade very quickly between the two on the same mushroom, and often the pale form has an area of the dark brown or a dark reddish brown in the center, or there are streaks of the darker colors. You can see a variety of color forms in the single group of them in these pictures.
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Amanita brunnescens group, with stained (brown) stems
Photo by Eric Smith
Amanita citrina
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Amanita citrina
Illustration from Eugen Gramberg’s Pilze userer Heimat (1936)
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Amanita citrina group
Photo by Eric Smith
There are actually quite a few color variations for “citrina.” Some of them even turn lilac when cut. The stem may also bruise brown if it doesn’t bruise lilac. Because of these variable reactions, there has been longstanding speculation that we might have more than one species of “citrina”. For the moment, the DNA is saying that we have at least three distinct species in the east, but they’re not necessarily coordinated with the lilac tinges – rather, the lilac may be a reaction to cold weather. But for the moment, the only official name available for them is A. citrina.
Amanita porphyria
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Amanita porphyria, showing purplish-brown cap with purplish-gray universal veil material
Photo by Darvin DeShazer
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Amanita porphyria, showing gray ring
Photo by Eric Smith
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Amanita porphyria
Photo by Pam Kaminski
This is the one mushroom in the group that is found throughout North America. Well, they’re probably not all the same species, but mushrooms corresponding to this species concept are certainly found all over the continent. Some graduate student will probably sort them all out in about 40 years.
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Amanita porphyria – did I mention that this mushroom can be all sorts of shades or reddish/purplish brown on top, with different shades of purplish gray universal veil material?
Photo by Darvin Deshazer
Amanita solaniolens
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Amanita solaniolens is the most gracile mushroom of this group.
Photo by Eric Smith
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Amanita solaniolens, the greener color form
Photo by Eric Smith
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A slender brown A. solaniolens