Angel wing

Pleurocybella porrigens

''Pleurocybella porrigens'' is a species of fungus in the Marasmiaceae family. The species is widespread in temperate forests of the Northern Hemisphere. ''P. porrigens'', known as the angel wing, is a white-rot wood-decay fungus on conifer wood, particularly hemlock. The flesh is thin and fragile compared to the oyster mushrooms.
Angel Wings (Oyster Mushrooms) Though they look a bit like shelf bracket fungus, these were soft and wet more like a mushroom. Update - saw more of these and was able to identify them as a variety of Oyster mushroom Geotagged,Pleurocybella porrigens,United States

Defense

Although ''P. porrigens'' is generally regarded as edible, as of 2011, it has been implicated in two documented outbreaks involving fatal encephalopathy. Both incidents were in Japan, and most victims had pre-existing kidney disorders.

The first incident occurred in September and October 2004 across nine prefectures in Japan, and involved the sickening of 59 people and the eventual death of 17. Most of those who died had pre-existing liver problems, and the average age of those affected was 70. Death occurred between 13 and 29 days after the onset of symptoms, and the onset of symptoms occurred at most three weeks after consumption of ''P. porrigens''.

The second incident occurred in 2009, when a 65-year-old man who had been on hemodialysis died from acute encephalopathy after eating ''P. porrigens''.

The mechanism of action for the toxicity of ''P. porrigens'' has not been definitively established, but several possibilities have been suggested. It has been demonstrated that ''P. porrigens'' contains an unusual unstable amino acid which is toxic to the brain cells of rats in cell culture studies, but it has not yet been possible to definitively determine that this was the cause of the fatal encephalopathies. Other mechanisms have been suggested for ''P. porrigenss apparent toxicity, including the possibility that cyanide levels in ''P. porrigens'' may be high enough to be toxic.

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Taxonomy
KingdomFungi
DivisionBasidiomycota
ClassAgaricomycetes
OrderAgaricales
FamilyPhyllotopsidaceae
GenusPleurocybella
SpeciesP. porrigens