Common Fieldcap vs Rootless Duckweed

Agrocybe pediades compared with Wolffia arrhiza

Key Differences

Common Fieldcap is Least Concern while Rootless Duckweed is Endangered.

Taxonomic Classification

Rank	Common Fieldcap	Rootless Duckweed
Kingdom	Fungi (грибы)	Plantae (растения)
Phylum	Basidiomycota (базидиомицеты)	Magnoliophyta (магнолиофиты)
Class	Agaricomycetes (агарикомицеты)	Liliopsida (лилиопсиды)
Order	Agaricales (агариковые)	Alismatales (частухоцветные)
Family	Strophariaceae	Araceae
Genus	Agrocybe	Wolffia
Species	Agrocybe pediades	Wolffia arrhiza

Conservation Status

Common Fieldcap

LC — Least Concern

Rootless Duckweed

EN — Endangered

Physical Characteristics

Attribute	Common Fieldcap	Rootless Duckweed
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).

Rootless Duckweed

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, temperate broadleaf and mixed forests, and temperate coniferous forests, among 4 distinct biome types spanning the Indomalayan and Oceanian and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Japan), Europe (10 countries), North America (Canada), and South America (Brazil). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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.