Common Frillwort vs small tortoiseshell

Fossombronia pusilla compared with Aglais urticae

Key Differences

• Common Frillwort is Critically Endangered while small tortoiseshell is Near Threatened.

Taxonomic Classification

Rank	Common Frillwort	small tortoiseshell
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Marchantiophyta (liverwort)	Arthropoda (Arthropods)
Class	Jungermanniopsida (Jungermanniopsida)	Insecta (Insects)
Order	Fossombroniales (Fossombroniales)	Lepidoptera (Butterflies & Moths)
Family	Fossombroniaceae	Nymphalidae (Brush-footed Butterflies)
Genus	Fossombronia	Aglais
Species	Fossombronia pusilla	Aglais urticae

Conservation Status

Common Frillwort

CR — Critically Endangered

small tortoiseshell

NT — Near Threatened

Physical Characteristics

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

Habitat & Geographic Range

Common Frillwort

Habitat

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

Range

Found across Asia (Taiwan) and Europe (5 countries). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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 Frillwort

<em>Fossombronia pusilla</em>, commonly known as the common frillwort, is a small liverwort belonging to the family Fossombroniaceae within the division Marchantiophyta. This non-vascular bryophyte typically grows in moist, disturbed soils, clay banks, and damp pathways across its range in Europe and parts of Asia. The thallus is typically lobed and frilly in appearance, giving the species its common name. <em>Fossombronia pusilla</em> favors habitats with high moisture and reduced competition, often colonizing bare or sparsely vegetated ground following disturbance. Its geographic range spans temperate regions of western and central Europe into Asia, though populations have become increasingly fragmented. The species is currently assessed as Critically Endangered on the IUCN Red List, reflecting severe population declines likely driven by habitat loss, land drainage, and agricultural intensification. Biological traits such as lifespan, body size, and diet remain poorly documented for this species, as is common among many small bryophyte taxa. Like other liverworts, <em>Fossombronia pusilla</em> reproduces both sexually through spores and vegetatively. Conservation of this species depends on protecting moist, low-competition microhabitats and reducing disturbance to its specialized substrates.

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 🇱🇺 Luxembourg 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden