Common Earthball vs small tortoiseshell

Scleroderma citrinum compared with Aglais urticae

Key Differences

• Common Earthball is Least Concern while small tortoiseshell is Near Threatened.

Taxonomic Classification

Rank	Common Earthball	small tortoiseshell
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Basidiomycota (Club Fungi)	Arthropoda (Arthropods)
Class	Agaricomycetes (Mushrooms)	Insecta (Insects)
Order	Boletales (Boletales)	Lepidoptera (Butterflies & Moths)
Family	Sclerodermataceae	Nymphalidae (Brush-footed Butterflies)
Genus	Scleroderma	Aglais
Species	Scleroderma citrinum	Aglais urticae

Conservation Status

Common Earthball

LC — Least Concern

small tortoiseshell

NT — Near Threatened

Physical Characteristics

Attribute	Common Earthball	small tortoiseshell
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Earthball

Habitat

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

Range

Widely distributed across Asia (Taiwan), Europe (5 countries), North America (United States), and South America (Brazil, Chile).

small tortoiseshell

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Found across Europe (41 countries). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Common Earthball

<em>Scleroderma citrinum</em>, commonly known as the common earthball or pigskin poison puffball, is a widespread ectomycorrhizal fungus in the family Sclerodermataceae, classified as Least Concern by the IUCN. The species occurs across Asia, Europe, North America, and South America, typically found on forest floors, decomposing wood, and mineral-rich acidic soils in association with hardwood and conifer tree roots. Unlike true puffballs, <em>Scleroderma citrinum</em> is considered poisonous and should not be confused with edible species. Its thick, warty outer skin ranges from yellowish-brown to ochre and encloses a dark purplish-black spore mass that matures over time. The species plays an important ecological role as a mycorrhizal partner, forming mutualistic associations with the roots of oaks, beeches, pines, and other trees, facilitating the uptake of water and nutrients by host plants in exchange for photosynthetically derived carbon. Fruiting bodies typically emerge from late summer through autumn, releasing spores through irregular cracks or a central apical opening when mature. <em>Scleroderma citrinum</em> is a host for the parasitic fungus <em>Pseudoboletus parasiticus</em>, making it ecologically significant within forest fungal communities. Biological traits of this species remain poorly documented in the scientific literature.

small tortoiseshell

small tortoiseshell (Aglais urticae) is classified as Near Threatened (NT) on the IUCN Red List. Close to qualifying as threatened, with populations that may become vulnerable without conservation action.

Shared Countries

Both species can be found in 5 countries:

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