Verdigris agaricStropharia aeruginosa

The verdigris agaric (Stropharia aeruginosa) is a distinctive bright green-blue mushroom with a prominent ring on the stem, one of the most recognizable species in the family Strophariaceae. The Latin epithet aeruginosa (as in Russula aeruginea) means "copper-green, verdigris-green" — a perfect description of its unique color. The cap is 3-8 cm across, convex-bell-shaped when young, flattening with age with a low hump, strikingly blue-green to bluish green, with a characteristic metallic sheen in wet weather, and as it fades it turns yellowish with a greenish tint.

Inedible — in Ukrainian and European tradition it is listed as inedible or conditionally edible after boiling, and some sources mention risks of gastrointestinal upset and mildly psychoactive effects (the species is closely related to psychoactive Stropharia and Psilocybe, contains trace amounts of psilocybin in some populations — not enough for a pronounced effect, but enough for an unpredictable reaction in some people).

Current recommendation — DO NOT EAT: (1) unpredictable psychoactivity in some fruiting bodies; (2) possible gastrointestinal upset; (3) its legal status is unclear in various European countries because of its kinship with controlled species; (4) little culinary value; (5) there are plenty of unquestionably safe mushrooms.

Key features of Stropharia aeruginosa: A strikingly blue-green cap with a metallic sheen in wet weather Slimy, sticky cap skin in wet weather A membranous ring on the stem (often with purple-black spore deposits) Dark violet gills in mature specimens Spore print dark violet-black — typical of the genus Flesh pale greenish white Smell faint, mushroomy, with a hint of radish Grows in broadleaf and mixed forests on rotting leaves and forest litter, sometimes on decaying wood

The main risk is confusing it with Stropharia caerulea (rarer, also blue-green, with no ring or only a rudimentary one) and with young toxic psychoactive Psilocybe semilanceata (much smaller, with a pointed knob). The key check — the spore print is dark violet-black in Stropharia.

In Ukraine, Stropharia aeruginosa is common in broadleaf and mixed forests: the Carpathians, the Carpathian foothills, Polissia, the forest-steppe. Season: August — November.