Clouded slender vs Eurasian beaver

Caloptilia populetorum compared with Castor fiber

Key Differences

• Clouded slender is Least Concern while Eurasian beaver is Vulnerable.

Taxonomic Classification

Rank	Clouded slender	Eurasian beaver
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Insecta (Insects)	Mammalia (Mammals)
Order	Lepidoptera (Butterflies & Moths)	Rodentia (Rodents)
Family	Gracillariidae	Castoridae (Beavers)
Genus	Caloptilia	Castor (Beavers)
Species	Caloptilia populetorum	Castor fiber

Evolutionary Relationship

Clouded slender and Eurasian beaver share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Clouded slender

LC — Least Concern

Eurasian beaver

VU — Vulnerable

Physical Characteristics

Attribute	Clouded slender	Eurasian beaver
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Clouded slender

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Found across Europe (6 countries).

Eurasian beaver

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found across Europe (6 countries). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Clouded slender

Clouded slender refers to a small moth in one of several microlepidopteran families characterized by narrow, elongated wings with clouded or mottled patterning, the 'slender' designation reflecting the elongated wing shape typical of gracillariid leaf miners, stathmopodid moths, or similar narrow-winged families. Slender moths of this type are often highly specialized as leaf miners or stem borers in their larval stage, with adults emerging in spring or summer from pupae formed within the mined leaf or on adjacent vegetation. The clouded wing pattern typically consists of subtle brown, grey, and cream mottling or diffuse cross-banding that provides camouflage against bark and foliage substrates. Many slender moth species in Europe and Asia have restricted distributions tied to the availability of specific larval host plants, making them sensitive to changes in plant community composition. Documentation of species through light trapping and larval rearing from identified host plants contributes to understanding the full diversity of microlepidoptera in temperate and subtropical habitats where hundreds of species remain incompletely studied.

Eurasian beaver

Eurasian beaver (Castor fiber) is classified as Vulnerable (VU) on the IUCN Red List. Facing a high risk of endangerment in the wild, with declining populations and increasing habitat pressure.

Shared Countries

Both species can be found in 5 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇷🇺 Russia 🇸🇪 Sweden