Common Fat-tailed Mouse Opossum vs Grayling

Thylamys pusillus compared with Hipparchia semele

Key Differences

• Common Fat-tailed Mouse Opossum is Least Concern while Grayling is Endangered.

Taxonomic Classification

Rank	Common Fat-tailed Mouse Opossum	Grayling
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Arthropoda (Arthropods)
Class	Mammalia (Mammals)	Insecta (Insects)
Order	Didelphimorphia (Didelphimorphia)	Lepidoptera (Butterflies & Moths)
Family	Didelphidae	Nymphalidae (Brush-footed Butterflies)
Genus	Thylamys	Hipparchia
Species	Thylamys pusillus	Hipparchia semele

Evolutionary Relationship

Common Fat-tailed Mouse Opossum and Grayling share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Fat-tailed Mouse Opossum

LC — Least Concern

Grayling

EN — Endangered

Physical Characteristics

Attribute	Common Fat-tailed Mouse Opossum	Grayling
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Fat-tailed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Grayling

Habitat

Inhabits temperate broadleaf and mixed forests and Mediterranean forests and woodlands within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found across Europe (37 countries). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Fat-tailed Mouse Opossum

The Common Fat-tailed Mouse Opossum (<em>Thylamys pusillus</em>) is a small marsupial belonging to the genus Thylamys within the family Didelphidae. Like other members of its genus, this species typically stores fat in its tail, which becomes swollen during periods of food abundance and is metabolised during leaner times, a physiological adaptation that provides energy reserves. <em>Thylamys pusillus</em> is generally found in diverse terrestrial and aquatic ecosystems, often in dry woodlands, scrublands, and grassland habitats of South America. The species is assessed as Least Concern on the IUCN Red List, indicating it is not currently considered at risk of extinction. Detailed geographic range data are not available in the current record, but members of this genus are typically distributed across parts of Argentina, Bolivia, Paraguay, and Uruguay. Biological traits including average lifespan, body dimensions, and specific dietary composition remain poorly documented in the scientific literature, though Thylamys species are generally considered omnivorous, often consuming insects, small vertebrates, and plant material.

Grayling

Grayling (Hipparchia semele) is classified as Endangered (EN) on the IUCN Red List. At high risk of extinction in the wild, with significant population decline and ongoing threats to survival.