Amanita phalloides - Deathcap

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

This largish fungus, known infamously and justifiably as the Deathcap, accounts for more than 90% of fungus-related poisoning deaths in Europe. Amanita phalloides is quite a common species in most parts of Britain and Ireland.

The common name is sometimes written as Death Cap, and in the USA (to where this species was almost certainly introduced from Europe) this toxic toadstool is referred to as the Death Cup.

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Animal feeding behaviour has generally been used as the first indication of the edibility of plants and fungi. This can be a treacherous guide, however, as rabbits and squirrels appear to be unaffected by Amanita phalloides and many other fungi that can seriously harm or even kill people.

The Deathcap, Amanita phalloides, was known by the ancient Greeks and Romans to be a deadly poison. It has been a favourite of poisoners down the centuries, and even nowadays it is still the cause of tragic and painful deaths every year.

Colours vary from sample to sample, but the most common form of this fungus has a pale yellow-green or olive cap. There is, however, an all-white form of Amanita phalloides that is very similar in appearance to the Destroying Angel, Amanita virosa. Young Deathcap specimens are sometimes collected in mistake for edible Agaricus mushrooms, with disastrous consequences.

Identification guide

	Cap 5 - 15cm dia; almost white when immature, then yellow, bronze or olive, darker in the centre (occasionally deep grass green shading towards black at the centre); soon losing all fragments of the universal veil; initially egg-shaped, but flattening at maturity. The cap, which is not striate at the margin, tends to crack at the edges when very old. As they decay, Amanita phalloides fungi give off an unpleasant smell.
	Gills Free, broad and crowded. Initially the gills are pure white, but they turn cream as the fruit body ages.
	Stem Stem height 7 - 15cm; off-white, with zig-zag mottling somewhat paler than the cap colour. Amanita phalloides usually retain their fragile, pendant ring through to maturity. The swollen base is surrounded by a large white, sack-like volva that is often tinged green inside.
Spore print	White
Odour/taste	Not distinctive when young, but old specimens have an unpleasant sickly sweet smell. Do not attempt to taste this deadly poisonous species.
Habitat	Mycorhizal with hardwood, especially oaks, and occasionally with softwood trees; most common at low altitude.
Season	July to November.
Occurrence	Frequent.
Similar species	Amanita citrina (False Deathcap) generally has brownish-cream veil fragments on the cap, and a volval rim around its base rather than an open sack-like volva. Agaricus campestris and other Agaricus mushrooms do not have volvae; also, the gills of immature Amanita phalloides fungi are not grey or pinky-brown as is the case with young Agaricus mushrooms.