vs Colombian Oldfield Mouse

Chrysococcus cordiformis compared with Thomasomys dispar

Key Differences

• is Not Evaluated while Colombian Oldfield Mouse is Data Deficient.

Taxonomic Classification

Rank		Colombian Oldfield Mouse
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Chordata (Chordates)
Class	Chrysophyceae (Chrysophyceae)	Mammalia (Mammals)
Order	Chromulinales (Chromulinales)	Rodentia (Rodents)
Family	Dinobryaceae	Cricetidae
Genus	Chrysococcus	Thomasomys
Species	Chrysococcus cordiformis	Thomasomys dispar

Conservation Status

NE — Not Evaluated

Colombian Oldfield Mouse

DD — Data Deficient

Physical Characteristics

Attribute		Colombian Oldfield Mouse
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

Colombian Oldfield Mouse

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Colombia.

Chrysococcus cordiformis is a freshwater chrysophyte microalga in the genus Chrysococcus, class Chrysophyceae. The species epithet cordiformis — heart-shaped — describes the characteristic lorica shape of this species, a lorica being the rigid or semi-rigid outer case secreted by the cell that gives Chrysococcus its distinctive appearance. The heart-shaped lorica of C. cordiformis provides a clear morphological character distinguishing it from species with spherical, ovoid, or otherwise shaped loricas. Chrysococcus species are unicellular, loricate golden algae that inhabit freshwater ecosystems, particularly the euphotic zones of oligotrophic to mesotrophic lakes and ponds. C. cordiformis has been documented from Norwegian and Swedish freshwater environments, which provide cold, clear-water habitats typical of Scandinavian highland and boreal lakes. Records also extend to Brazil, indicating a wide geographic range consistent with the passive dispersal capacity of small, light-weight planktonic microalgae. The cells of C. cordiformis possess one or two flagella that protrude through an opening in the lorica, enabling active swimming in the water column. Photosynthesis is conducted using chlorophylls a and c with carotenoid accessory pigments. Chrysococcus species may also feed phagotrophically on bacteria. C. cordiformis has not been formally evaluated under IUCN criteria and retains a conservation status of Not Evaluated. It represents a characteristic member of freshwater chrysophyte communities associated with cool, acidic, or nutrient-poor Scandinavian lake systems.

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.