Серо-желтый опёнок (Hypholoma fasciculare) – ядовитый гриб

Species of fungus

Hypholoma fasciculare, commonly known as the sulphur tuft or clustered woodlover, is a common woodland mushroom, often in evidence when hardly any other mushrooms are to be found. This saprotrophic small gill fungus grows prolifically in large clumps on stumps, dead roots or rotting trunks of broadleaved trees. The "sulphur tuft" is bitter and poisonous; consuming it can cause vomiting, diarrhea and convulsions. The toxins are steroids known as fasciculols and have been shown to be calmodulin inhibitors.

The specific epithet is derived from the Latin fascicularis 'in bundles' or 'clustered', referring to its habit of growing in clumps. Its name in Japanese is Nigakuritake (苦栗茸, means "Bitter kuritake").

The hemispherical cap ranges from in diameter. It is smooth and sulphur yellow with an orange brown centre and whitish margin. The crowded gills are initially yellow but darken to a distinctive green colour as the blackish spores develop on the yellow flesh. It has a purple brown spore print. The stipe is tall and 4–10 mm wide, though not bitter when cooked, but still poisonous.

The edible Hypholoma capnoides is similar, but lacks the greenish yellow gills and bitter taste. and also eastern Anatolia in Turkey. It can appear anytime from spring to autumn.

The toxicity of sulfur tuft mushrooms has been attributed, at least partially, to the toxic steroids fasciculol E and fasciculol F (in mice, with LD50(i. p.) values of 50 mg/kg and 168 mg/kg, respectively). In humans, symptoms may be delayed for 5–10 hours after consumption, after which time there may be diarrhea, nausea, vomiting, proteinuria and collapse. Paralysis and impaired vision have been recorded. Symptoms generally resolve over a few days. The autopsy of one fatality revealed fulminant hepatitis reminiscent of amatoxin poisoning, along with involvement of kidneys and myocardium. The mushroom was consumed in a dish with other species so the death cannot be attributed to sulfur tuft with certainty. Extracts of the mushroom show anticoagulant effects.