Colombian Oldfield Mouse vs Heavy-browed Mouse Opossum

Thomasomys dispar compared with Marmosa andersoni

Taxonomic Classification

Rank	Colombian Oldfield Mouse	Heavy-browed Mouse Opossum
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Mammalia (Mammals)	Mammalia (Mammals)
Order	Rodentia (Rodents)	Didelphimorphia (Didelphimorphia)
Family	Cricetidae	Didelphidae
Genus	Thomasomys	Marmosa
Species	Thomasomys dispar	Marmosa andersoni

Evolutionary Relationship

Colombian Oldfield Mouse and Heavy-browed Mouse Opossum share a common ancestor at the Class level: Mammalia. (Mammals)

Conservation Status

Colombian Oldfield Mouse

DD — Data Deficient

Heavy-browed Mouse Opossum

DD — Data Deficient

Physical Characteristics

Attribute	Colombian Oldfield Mouse	Heavy-browed Mouse Opossum
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Colombian Oldfield Mouse

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Colombia.

Heavy-browed Mouse Opossum

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Colombian Oldfield Mouse

<em>Thomasomys dispar</em>, commonly known as the Colombian Oldfield Mouse, is a small rodent species belonging to the genus <em>Thomasomys</em> within the family Cricetidae. This species is classified as Data Deficient, indicating that insufficient information is currently available to evaluate its conservation status with confidence. It has been documented in Colombia, where it inhabits diverse terrestrial and aquatic-adjacent environments. Members of the genus <em>Thomasomys</em> are typically associated with high-altitude Andean habitats, including páramo grasslands, shrublands, and montane forest edges, where they occupy ground-level microhabitats and burrow in soft soils. These mice are generally omnivorous, consuming seeds, plant material, and invertebrates, though specific dietary data for <em>Thomasomys dispar</em> have not been recorded. Biological traits of this species remain poorly documented in the scientific literature. The Data Deficient classification highlights the need for targeted surveys in Colombian Andean regions to determine population size, distribution, and the ecological requirements of this poorly known rodent.