Common Fieldcap vs common grey sea slug

Agrocybe pediades compared with Aeolidia papillosa

Taxonomic Classification

Rank	Common Fieldcap	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	Strophariaceae	Aeolidiidae
Genus	Agrocybe	Aeolidia
Species	Agrocybe pediades	Aeolidia papillosa

Conservation Status

Common Fieldcap

LC — Least Concern

common grey sea slug

LC — Least Concern

Physical Characteristics

Attribute	Common Fieldcap	common grey sea slug
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Fieldcap

Habitat

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

Range

Found across Europe (5 countries) and North America (United States).

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.

Common Fieldcap

The Common Fieldcap (<em>Agrocybe pediades</em>) is a saprotrophic fungus belonging to the genus Agrocybe within the family Strophariaceae. It typically produces small, tan to pale brown cap-shaped fruiting bodies and is often found growing in clusters or scattered on lawns, grassy areas, forest floors, decomposing wood, and soil-rich ecosystems. The species typically inhabits forest floors, decomposing wood, and soil ecosystems, obtaining nutrients by breaking down dead organic matter. Its geographic range includes several European countries — Belgium, Denmark, Norway, Portugal, and Sweden — as well as the United States in North America. <em>Agrocybe pediades</em> is assessed as Least Concern on the IUCN Red List, reflecting its broad distribution and apparent stability. Biological traits of this species, including specific data on fruiting body size, lifespan, and ecological preferences, remain poorly documented in the scientific literature. Like other members of its genus, it typically fruits during warmer months and often appears after rainfall in nutrient-rich grassland and woodland habitats.

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