Common Fat-tailed Mouse Opossum vs Dark Stonewort

Thylamys pusillus compared with Nitella opaca

Taxonomic Classification

Rank	Common Fat-tailed Mouse Opossum	Dark Stonewort
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Chordata (Chordates)	Charophyta (Charophyta)
Class	Mammalia (Mammals)	Charophyceae (Charophyceae)
Order	Didelphimorphia (Didelphimorphia)	Charales (Charales)
Family	Didelphidae	Characeae
Genus	Thylamys	Nitella
Species	Thylamys pusillus	Nitella opaca

Conservation Status

Common Fat-tailed Mouse Opossum

LC — Least Concern

Dark Stonewort

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Common Fat-tailed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Dark Stonewort

Habitat

Native to Europe and North America and South America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Brazil, Denmark, Norway, Sweden, and United States.

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.