Brown Rat vs

Rattus norvegicus compared with Chrysococcus triporus

Key Differences

Brown Rat is Least Concern while is Not Evaluated.

Taxonomic Classification

Rank	Brown Rat
Kingdom	Animalia (Animals)	Chromista (Chromista)
Phylum	Chordata (Chordates)	Ochrophyta (Ochrophyta)
Class	Mammalia (Mammals)	Chrysophyceae (Chrysophyceae)
Order	Rodentia (Rodents)	Chromulinales (Chromulinales)
Family	Muridae (Mice & Rats)	Dinobryaceae
Genus	Rattus	Chrysococcus
Species	Rattus norvegicus	Chrysococcus triporus

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, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, 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.

Chrysococcus triporus is a unicellular freshwater chrysophyte microalga in the genus Chrysococcus, class Chrysophyceae. The species epithet triporus — three-pored — refers to the presence of three distinct pores in the lorica, the outer proteinaceous or polysaccharide envelope that encloses the Chrysococcus cell. Pore number and arrangement provide useful taxonomic characters in this genus, alongside lorica shape, surface texture, and the presence or absence of additional projections or ornamentation. C. triporus has been recorded from Norwegian and Swedish freshwater environments, fitting the established pattern of chrysophyte diversity in Scandinavian lakes and ponds. Records from Brazil suggest a broader distribution, though it is uncertain whether Scandinavian and South American populations represent a single species or cryptic lineages that require molecular resolution. The species inhabits the limnetic zone of freshwater bodies, contributing to primary production through photosynthesis with chlorophylls a and c and fucoxanthin pigments. The cell body is enclosed within the lorica from which one or two flagella emerge through a specialized opening, enabling active swimming in the water column. Chrysococcus species function as prey for ciliates, flagellates, and zooplankton, linking primary production to higher trophic levels in freshwater food webs. C. triporus may also produce siliceous stomatocysts as resting stages that can persist in sediments. The species has not been formally evaluated under IUCN criteria and retains a conservation status of Not Evaluated.