How to tell Fairy inkcap from Liberty cap

Young caps are egg-shaped, up to 8 mm, then bell-shaped, 0.5 to 1.5 cm across, occasionally 2 cm, opening only a little. They start cream with an ochre centre, later grey or greyish brown, the centre staying ochre.

The surface is pleated from the margin almost to the centre, and young caps are finely hairy and granular under a hand lens. The cap is very fragile.

The cap is small, 1-2.5 cm across, sharply conical or bell-shaped with a pronounced pointed knob in the centre, which gives it the epithet semilanceata ("half-lance-shaped"). The cap skin is smooth, slimy in wet weather, dry with lengthwise grooves in dry weather. The colour is ochre-cream; olive-brown with a greenish tint when wet, pale cream when dry. The pointed central knob is the most characteristic diagnostic feature.

The gills are attached and fairly widely spaced for an inkcap, white at first, then grey and blackish. They don't dissolve into ink, though they can soften in rain.

The spore print is black to blackish brown.

The gills are attached to the stem and moderately crowded. In young mushrooms they're greyish-cream, darkening to purplish-blackish as the spores mature. The spore print is dark purple-black, a diagnostic feature of the genus Psilocybe.

The stem is 1.5 to 4 cm tall, occasionally 5 to 6 cm, and 1 to 2 mm thick, white, translucent, hollow, very fragile, often curved, and finely downy when young. There's no ring or volva.

The stem is 5-10 cm tall and 0.15-0.3 cm thick, so very long and thin, often curved. The colour is yellow-cream to light brown, and the surface is smooth with fine lengthwise fibres. There is no ring, and this is essential. It often turns blue when damaged, a characteristic psilocybin reaction and one of the diagnostic tests.

The flesh is very thin, almost membranous, and fragile.

The flesh is very thin, soft, yellowish to greenish. It quickly turns blue to blue-green when cut or damaged, a characteristic reaction of psilocybin alkaloids on contact with air. The smell is faint, mealy in some populations.

The smell and taste aren't distinctive.

Faint, neutral or mealy, nothing distinctive. The smell is not a warning sign.