Common Fat-tailed Mouse Opossum vs Hairy-nosed otter

Thylamys pusillus compared with Lutra sumatrana

Key Differences

• Common Fat-tailed Mouse Opossum is Least Concern while Hairy-nosed otter is Endangered.

Taxonomic Classification

Rank	Common Fat-tailed Mouse Opossum	Hairy-nosed otter
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum same	Chordata (脊索動物)	Chordata (脊索動物)
Class same	Mammalia (哺乳類)	Mammalia (哺乳類)
Order	Didelphimorphia (Didelphimorphia)	Carnivora (ネコ目)
Family	Didelphidae	Mustelidae (Weasels & Otters)
Genus	Thylamys	Lutra (Otters)
Species	Thylamys pusillus	Lutra sumatrana

Evolutionary Relationship

Common Fat-tailed Mouse Opossum and Hairy-nosed otter share a common ancestor at the Class level: Mammalia. (哺乳類)

Conservation Status

Common Fat-tailed Mouse Opossum

LC — Least Concern

Hairy-nosed otter

EN — Endangered

Physical Characteristics

Attribute	Common Fat-tailed Mouse Opossum	Hairy-nosed otter
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Fat-tailed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Hairy-nosed otter

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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.