Common Fat-tailed Mouse Opossum vs Rat tail grass

Thylamys pusillus compared with Sporobolus elongatus

Key Differences

• Common Fat-tailed Mouse Opossum is Least Concern while Rat tail grass is Not Evaluated.

Taxonomic Classification

Rank	Common Fat-tailed Mouse Opossum	Rat tail grass
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Chordata (Chordates)	Magnoliophyta (Flowering Plants)
Class	Mammalia (Mammals)	Liliopsida (Monocots)
Order	Didelphimorphia (Didelphimorphia)	Poales (Grasses)
Family	Didelphidae	Poaceae (Grass Family)
Genus	Thylamys	Sporobolus
Species	Thylamys pusillus	Sporobolus elongatus

Conservation Status

Common Fat-tailed Mouse Opossum

LC — Least Concern

Rat tail grass

NE — Not Evaluated

Physical Characteristics

Attribute	Common Fat-tailed Mouse Opossum	Rat tail grass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Fat-tailed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Rat tail grass

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Europe (6 countries), North America (United States), and Oceania and the Pacific (Solomon Islands, Tonga, Vanuatu).

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.