Brown Rat vs

Rattus norvegicus compared with Colacium sideropus

Key Differences

• Brown Rat is Least Concern while is Not Evaluated.

Taxonomic Classification

Rank	Brown Rat
Kingdom	Animalia (Animals)	Protozoa (protozoa)
Phylum	Chordata (Chordates)	Euglenozoa (Euglenozoa)
Class	Mammalia (Mammals)	Euglenoidea (Euglenoidea)
Order	Rodentia (Rodents)	Euglenida (Euglenida)
Family	Muridae (Mice & Rats)	Euglenaceae
Genus	Rattus	Colacium
Species	Rattus norvegicus	Colacium sideropus

Conservation Status

Brown Rat

LC — Least Concern

NE — Not Evaluated

Physical Characteristics

Attribute	Brown Rat
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brown Rat

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 10 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (11 countries), Asia (15 countries), Europe (41 countries), North America (16 countries), Oceania and the Pacific (10 countries), and South America (10 countries).

Habitat

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

Range

Distributed across Brazil and Sweden.

Brown Rat

Brown Rat (Rattus norvegicus) is classified as Least Concern (LC) on the IUCN Red List. Widespread and abundant across its range, with stable populations and no immediate conservation concerns.

Colacium sideropus is a microscopic euglenoid protist belonging to the family Euglenaceae, characterized by its sessile, colonial lifestyle attaching to aquatic invertebrates and zooplankton. Members of the genus Colacium are distinguished from free-swimming euglenoids by their stalked or clustered growth form, anchoring to the bodies of crustaceans such as copepods and cladocerans in freshwater environments. Like other photosynthetic euglenoids, Colacium possesses chloroplasts derived from secondary endosymbiosis with a green alga, allowing it to perform photosynthesis under favorable light conditions. The relationship with host invertebrates is generally considered epibiotic rather than parasitic, with the protist colonizing the external surfaces of its host without causing significant harm. Colacium sideropus occurs in freshwater lakes, ponds, and slow-moving streams where its zooplankton hosts are abundant. Its ecological role includes contributing to microbial food webs and nutrient cycling within freshwater ecosystems. As with many microscopic protists, its true distribution and abundance are difficult to assess from macroscopic surveys, and it is likely globally distributed wherever suitable hosts exist in freshwater habitats.

Shared Countries

Both species can be found in 2 countries:

🇧🇷 Brazil 🇸🇪 Sweden