This relatively common fungus has accounted for more deaths than any other poisonous toadstool found in the British Isles. If you suspect that someone has accidentally eaten any of this fungus, take them and, if possible, a sample of the fungus straight to a hospital for emergency treatment. The cap, which is various shades of olive or yellowish green, reaches a diameter of 6 to 12 cm.
Old specimens give off an unpleasant smell.
Death caps are most commonly found in broad-leaved woods, but they do also occur under conifers. They are found in late summer and autumn.