Common Fieldcap vs Common Tarcrust

Agrocybe pediades compared with Diatrype stigma

Key Differences

• Common Fieldcap is Least Concern while Common Tarcrust is Not Evaluated.

Taxonomic Classification

Rank	Common Fieldcap	Common Tarcrust
Kingdom same	Fungi (Fungi)	Fungi (Fungi)
Phylum	Basidiomycota (Club Fungi)	Ascomycota (Sac Fungi)
Class	Agaricomycetes (Mushrooms)	Sordariomycetes (Sordariomycetes)
Order	Agaricales (Gilled Mushrooms)	Xylariales (Xylariales)
Family	Strophariaceae	Diatrypaceae
Genus	Agrocybe	Diatrype
Species	Agrocybe pediades	Diatrype stigma

Evolutionary Relationship

Common Fieldcap and Common Tarcrust share a common ancestor at the Kingdom level: Fungi. (Fungi)

Conservation Status

Common Fieldcap

LC — Least Concern

Common Tarcrust

NE — Not Evaluated

Physical Characteristics

Attribute	Common Fieldcap	Common Tarcrust
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 Tarcrust

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Belgium, Denmark, Norway, Portugal, 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 Tarcrust

<em>Diatrype stigma</em>, the common tarcrust, is a saprotrophic fungus in the family Diatrypaceae, found across Belgium, Denmark, Norway, Portugal, and Sweden, as well as more broadly in Europe and temperate regions globally. It grows as a crust-like, charcoal-black stromata on the dead bark and branches of deciduous hardwoods, particularly hazel, beech, and alder. The fruiting bodies are typically flat to slightly raised, dark gray to black patches that contain numerous embedded perithecia in which ascospores are produced. This fungus plays an important ecological role as a decomposer, breaking down dead woody material and recycling nutrients in forest ecosystems. It is Not Evaluated on the IUCN Red List; given its broad distribution on common substrates, it is generally considered widespread. The species reproduces via wind-dispersed ascospores released from the perithecia. Diet, as a saprotrophic organism, consists of dead organic woody matter. Biological traits such as colony growth rates, spore output, and longevity remain poorly documented in standardized quantitative assessments.

Shared Countries

Both species can be found in 5 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden