Colombian Oldfield Mouse vs Common Eurasian spadefoot toad

Thomasomys dispar compared with Pelobates fuscus

Key Differences

• Colombian Oldfield Mouse is Data Deficient while Common Eurasian spadefoot toad is Critically Endangered.

Taxonomic Classification

Rank	Colombian Oldfield Mouse	Common Eurasian spadefoot toad
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Amphibia (Amphibians)
Order	Rodentia (Rodents)	Anura (Frogs & Toads)
Family	Cricetidae	Pelobatidae
Genus	Thomasomys	Pelobates
Species	Thomasomys dispar	Pelobates fuscus

Evolutionary Relationship

Colombian Oldfield Mouse and Common Eurasian spadefoot toad share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Colombian Oldfield Mouse

DD — Data Deficient

Common Eurasian spadefoot toad

CR — Critically Endangered

Physical Characteristics

Attribute	Colombian Oldfield Mouse	Common Eurasian spadefoot toad
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.

Common Eurasian spadefoot toad

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 8 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Belgium, Denmark, Luxembourg, Russia, and Sweden. Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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.

Common Eurasian spadefoot toad

<em>Pelobates fuscus</em>, the common Eurasian spadefoot toad, is a fossorial amphibian in the family Pelobatidae, listed as Critically Endangered by the IUCN Red List, reflecting severe population declines and an urgent conservation status across its range. The species is documented in Belgium, Denmark, Luxembourg, Russia, and Sweden, and is associated with multiple biome types in the Palearctic region, typically favoring sandy, loose soils in agricultural landscapes, sandy heathlands, and open forests that facilitate its burrowing lifestyle. <em>Pelobates fuscus</em> spends the majority of its life underground, emerging primarily during the breeding season in spring to migrate to shallow, well-vegetated ponds, ditches, and slow-moving waterbodies for reproduction. The species is characterized by its smooth, mottled skin, large golden or yellowish eyes with vertical pupils, and the hardened metatarsal tubercle on each hind foot that serves as a digging tool. Tadpoles of this species are unusually large and can take up to five months to metamorphose. Primary threats include habitat loss through land-use change, drainage of breeding ponds, agricultural intensification, road mortality during migration, and degradation of sandy habitats essential for burrowing. Conservation efforts focus on habitat restoration and the creation of wildlife corridors. Biological traits of this species remain poorly documented in the scientific literature.