Collared Parachute vs common grey sea slug

Marasmius rotula compared with Aeolidia papillosa

Taxonomic Classification

Rank	Collared Parachute	common grey sea slug
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Basidiomycota (Club Fungi)	Mollusca (Mollusks)
Class	Agaricomycetes (Mushrooms)	Gastropoda (Gastropoda)
Order	Agaricales (Gilled Mushrooms)	Nudibranchia (Nudibranchia)
Family	Marasmiaceae	Aeolidiidae
Genus	Marasmius	Aeolidia
Species	Marasmius rotula	Aeolidia papillosa

Conservation Status

Collared Parachute

LC — Least Concern

common grey sea slug

LC — Least Concern

Physical Characteristics

Attribute	Collared Parachute	common grey sea slug
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Collared Parachute

Habitat

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

Range

Widely distributed across Europe (4 countries), North America (United States), and South America (Brazil).

common grey sea slug

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Distributed across Belgium, Chile, Denmark, Norway, and Sweden.

Collared Parachute

The Collared Parachute, known scientifically as <em>Marasmius rotula</em>, is a small saprotrophic fungus belonging to the family Marasmiaceae within the order Agaricales. <em>Marasmius rotula</em> is characterised by its distinctive wheel-like or parachute-shaped cap, which typically features radial gill-like ridges connected to a collar around the stipe rather than attaching directly to it — a feature that gives the species both its common and scientific names. This species typically grows on decomposing leaf litter, dead woody material, and forest floors in deciduous and mixed woodland. It is reported to occur in Belgium, Brazil, Denmark, Norway, and Sweden. As a decomposer, <em>Marasmius rotula</em> plays a role in nutrient cycling within forest ecosystems. Detailed biological traits including typical lifespan measures and physical dimensions are poorly documented for this species in available literature. The Collared Parachute is currently assessed as Least Concern on the IUCN Red List.

common grey sea slug

<em>Aeolidia papillosa</em>, commonly known as the common grey sea slug, is a nudibranch mollusc belonging to the genus Aeolidia within the family Aeolidiidae. Despite the species name referencing terrestrial and aquatic habitats including forests and freshwater, <em>Aeolidia papillosa</em> is primarily a marine organism. Its range includes Belgium, Chile, Denmark, Norway, and Sweden, indicating a distribution across the North Atlantic and into South American waters. Common grey sea slug is assessed as Least Concern on the IUCN Red List. The species is typically found in intertidal and subtidal zones, where it preys on sea anemones and stores stinging cells from its prey in its dorsal cerata for defense. Biological traits of this species remain poorly documented in the scientific literature.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden