Cottontail Foam Lichen vs Rock Foam

Stereocaulon paschale compared with Stereocaulon saxatile

Key Differences

• Cottontail Foam Lichen is Critically Endangered while Rock Foam is Near Threatened.

Taxonomic Classification

Rank	Cottontail Foam Lichen	Rock Foam
Kingdom same	Fungi (เห็ดรา)	Fungi (เห็ดรา)
Phylum same	Ascomycota (Sac Fungi)	Ascomycota (Sac Fungi)
Class same	Lecanoromycetes (Lecanoromycetes)	Lecanoromycetes (Lecanoromycetes)
Order same	Lecanorales (Lecanorales)	Lecanorales (Lecanorales)
Family same	Stereocaulaceae	Stereocaulaceae
Genus same	Stereocaulon	Stereocaulon
Species	Stereocaulon paschale	Stereocaulon saxatile

Evolutionary Relationship

Cottontail Foam Lichen and Rock Foam share a common ancestor at the Genus level: Stereocaulon.

Conservation Status

Cottontail Foam Lichen

CR — Critically Endangered

Rock Foam

NT — Near Threatened

Physical Characteristics

Attribute	Cottontail Foam Lichen	Rock Foam
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cottontail Foam Lichen

Habitat

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

Range

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

Rock Foam

Habitat

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

Range

Distributed across Denmark, Norway, Sweden, and United States. Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Shared Countries

Both species can be found in 4 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden 🇺🇸 United States