Eurasian beaver vs Simons’s Mouse Opossum

Castor fiber compared with Marmosa simonsi

Key Differences

• Eurasian beaver is Vulnerable while Simons’s Mouse Opossum is Not Evaluated.

Taxonomic Classification

Rank	Eurasian beaver	Simons’s Mouse Opossum
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Mammalia (Mammals)	Mammalia (Mammals)
Order	Rodentia (Rodents)	Didelphimorphia (Didelphimorphia)
Family	Castoridae (Beavers)	Didelphidae
Genus	Castor (Beavers)	Marmosa
Species	Castor fiber	Marmosa simonsi

Evolutionary Relationship

Eurasian beaver and Simons’s Mouse Opossum share a common ancestor at the Class level: Mammalia. (Mammals)

Conservation Status

Eurasian beaver

VU — Vulnerable

Simons’s Mouse Opossum

NE — Not Evaluated

Physical Characteristics

Attribute	Eurasian beaver	Simons’s Mouse Opossum
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

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.

Simons’s Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Ecuador.

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.