vs Common Fat-tailed Mouse Opossum

Chrysosphaerella triangulata compared with Thylamys pusillus

Key Differences

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

Taxonomic Classification

Rank		Common Fat-tailed Mouse Opossum
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Chordata (Chordates)
Class	Chrysophyceae (Chrysophyceae)	Mammalia (Mammals)
Order	Ochromonadales (Ochromonadales)	Didelphimorphia (Didelphimorphia)
Family	Paraphysomonadaceae	Didelphidae
Genus	Chrysosphaerella	Thylamys
Species	Chrysosphaerella triangulata	Thylamys pusillus

Conservation Status

NE — Not Evaluated

Common Fat-tailed Mouse Opossum

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Common Fat-tailed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Chrysosphaerella triangulata is a colonial freshwater chrysophyte microalga in the genus Chrysosphaerella, class Chrysophyceae, order Chromulinales. Chrysosphaerella species form spherical free-floating colonies of golden-brown cells embedded in a gelatinous matrix, with individual cells bearing elongated siliceous scales that project outward from the colony surface. The species epithet triangulata — triangular — refers to the triangular cross-section or profile of the siliceous scales on the cell surface, which distinguishes this species from C. annulata, which has annular ring structures on its scales, and from other congeners with different scale geometries. Siliceous scale morphology examined under scanning electron microscopy is the primary diagnostic character for Chrysosphaerella species identification. C. triangulata has been recorded from Norwegian and Swedish freshwater habitats, part of the documented chrysophyte flora of boreal and subarctic Scandinavian lakes. These environments are characterized by cold, clear, nutrient-poor water and seasonal ice cover, creating conditions favorable for chrysophyte diversity including colonial forms like Chrysosphaerella. The colonies inhabit the photic zone of the water column, photosynthesizing with chlorophylls a and c and carotenoid accessory pigments. Chrysosphaerella scales deposited in lake sediments serve as paleolimnological indicators. C. triangulata has not been formally evaluated under IUCN criteria and is listed as Not Evaluated. It contributes to documentation of the rich chrysophyte diversity in Scandinavian freshwater systems.

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.