vs Fly Agaric

Cliostomum leprosum compared with Amanita muscaria

Key Differences

• is Vulnerable while Fly Agaric is Least Concern.

Taxonomic Classification

Rank		Fly Agaric
Kingdom same	Fungi (Fungi)	Fungi (Fungi)
Phylum	Ascomycota (Sac Fungi)	Basidiomycota (Club Fungi)
Class	Lecanoromycetes (Lecanoromycetes)	Agaricomycetes (Mushrooms)
Order	Lecanorales (Lecanorales)	Agaricales (Gilled Mushrooms)
Family	Ramalinaceae	Agaricaceae (Agarics)
Genus	Cliostomum	Amanita (Amanitas)
Species	Cliostomum leprosum	Amanita muscaria

Evolutionary Relationship

and Fly Agaric share a common ancestor at the Kingdom level: Fungi. (Fungi)

Conservation Status

VU — Vulnerable

Fly Agaric

LC — Least Concern

Trend: Stable →

Physical Characteristics

Attribute		Fly Agaric
Diet	—	Decomposer
Average Lifespan	—	1 years
Average Length	—	20 cm
Average Weight	—	100 g

Habitat & Geographic Range

Habitat

Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway, Sweden, and United States. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Fly Agaric

Habitat

Typically found in forest floors, decomposing wood, and soil ecosystems.

Range

Widely distributed across Europe (4 countries), North America (United States), Oceania and the Pacific (New Zealand), and South America (Brazil, Chile, Colombia).

Cliostomum leprosum is a crustose lichen-forming fungus in the family Ramalinaceae, notable for its powdery, leprose thallus that gives it a granular, mealy appearance on bark and wood substrates. Unlike many lichens that form well-defined, structured thalli, C. leprosum produces a loosely coherent sorediose crust ranging from pale greenish-grey to whitish, often colonizing deeply shaded, moist bark on deciduous and coniferous trees. The species is distributed across boreal and temperate forests of Europe and North America, with confirmed records from Norway, Sweden, and scattered locations in the United States. It photosynthesizes in partnership with green algal partners typical of crustose lichens. Cliostomum leprosum is assessed as Vulnerable due to its sensitivity to air pollution, particularly sulfur dioxide and nitrogen compounds that degrade lichen communities. Its decline is linked to habitat loss from intensive forestry, removal of veteran trees, and acidic deposition. Conservation efforts focus on preserving old-growth and semi-natural forest stands that provide suitable, low-disturbance bark microhabitats where this inconspicuous but ecologically significant lichen can persist.

Fly Agaric

Among the most iconic and recognizable fungi on Earth, fly agaric mushrooms display striking red caps with white flecked warts across boreal forests of the Northern Hemisphere. Despite their fairy-tale appearance, they contain potent psychoactive compounds including muscimol and ibotenic acid and are moderately toxic. They form critical mycorrhizal symbioses with birch, pine, and spruce trees, exchanging mineral nutrients for carbon and playing essential roles in boreal forest nutrient cycling.

Shared Countries

Both species can be found in 3 countries:

🇳🇴 Norway 🇸🇪 Sweden 🇺🇸 United States