Hypholoma fasciculare

Sulphur tuft · Clustered woodlover

Toxic

Grows in dense clusters on stumps and wood chips, in the same habitat and season as P. cyanescens, and its bright sulphur-yellow to greenish colouring is nothing like a Psilocybe. Included mainly because it is abundant in the same beds and gets collected by accident in a mixed handful.

Several dense clusters of sulphur tuft growing from a mossy tree stump among fallen leaves, with sulphur-yellow caps that are orange in the centre and slender yellow stems joined at the base. — Photo: Norbert Nagel / Wikimedia Commons, CC BY-SA 3.0, source.

What it does

Toxin: Fasciculol steroids and related compounds.
Time to symptoms: Within a few hours.
Outcome: Severe vomiting and diarrhoea, occasionally with liver enzyme disturbance. Rarely fatal but thoroughly unpleasant. Intensely bitter, so most people spit it out.

Decisive characters

Each of these settles the question on its own. If one says no, the answer is no, regardless of what everything else says.

Colour

Psilocybin speciesCaramel to chestnut brown, drying pale

Look-alikeBright sulphur-yellow to yellow-green cap, greenish-yellow gills

Taste

Psilocybin speciesMild, farinaceous

Look-alikeIntensely, immediately bitter

Bruising

Psilocybin speciesBlue

Look-alikeNo blue reaction

Supporting characters

Useful corroboration. Not sufficient alone.

Spore print

Psilocybin speciesDark purple-brown

Look-alikePurple-brown as well. This one does NOT separate them

Confused with

Psilocybe cyanescens
Spore print: Dark purple-brown

Other look-alikes to know

Other mushrooms that get mistaken for the same psilocybin species. Learn the decisive characters for each, and see the full look-alikes guide.

Sources

[1]Hypholoma fasciculare toxicity, Bresinsky & Besl, A Colour Atlas of Poisonous Fungi (1990)

How we research this: sources, evidence grading, review and updates.