Common Flat-body vs Mourning Cloak

Agonopterix heracliana compared with Nymphalis antiopa

Key Differences

Common Flat-body is Least Concern while Mourning Cloak is Critically Endangered.

Taxonomic Classification

Rank	Common Flat-body	Mourning Cloak
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Arthropoda (Arthropods)	Arthropoda (Arthropods)
Class same	Insecta (Insects)	Insecta (Insects)
Order same	Lepidoptera (Butterflies & Moths)	Lepidoptera (Butterflies & Moths)
Family	Depressariidae	Nymphalidae (Brush-footed Butterflies)
Genus	Agonopterix	Nymphalis
Species	Agonopterix heracliana	Nymphalis antiopa

Evolutionary Relationship

Common Flat-body and Mourning Cloak share a common ancestor at the Order level: Lepidoptera. (Butterflies & Moths)

View Order: Lepidoptera

Conservation Status

Common Flat-body

LC — Least Concern

Mourning Cloak

CR — Critically Endangered

Physical Characteristics

Attribute	Common Flat-body	Mourning Cloak
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Flat-body

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Mourning Cloak

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 9 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found across Europe (39 countries) and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Flat-body

<em>Agonopterix heracliana</em> is a moth belonging to the family Depressariidae within the order Lepidoptera. Commonly known as the common flat-body, this species is named for the flattened resting posture characteristic of the genus Agonopterix. The species is classified as Least Concern on the IUCN Red List, with no indication of significant population decline. <em>Agonopterix heracliana</em> is distributed across northwestern Europe, with documented occurrences in Belgium, Denmark, Norway, and Sweden. Larvae of this species are typically associated with plants in the family Apiaceae, particularly hogweed (Heracleum sphondylium) and related umbellifers, upon which they feed while sheltering in rolled or folded leaves. Adults are typically brownish with subtle markings and are active from late summer through winter and early spring, overwintering as adults — an unusual life history trait among moths. The species inhabits hedgerows, woodland margins, and meadows where its host plants are abundant. Biological traits of this species remain poorly documented in the scientific literature.

Mourning Cloak

Mourning Cloak (Nymphalis antiopa) is classified as Critically Endangered (CR) on the IUCN Red List. Facing an extremely high risk of extinction in the wild due to severe population decline and habitat loss.