Brown Rat vs

Rattus norvegicus compared with Chrysococcus granulatus

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 granulatus

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 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 granulatus is a unicellular freshwater chrysophyte microalga in the genus Chrysococcus, class Chrysophyceae. The species epithet granulatus — granular or granulated — describes a textured surface on the lorica of this species, a feature visible under electron microscopy that contrasts with the smooth surfaces of some congeners. In the genus Chrysococcus, the lorica is a secreted outer covering enclosing the cell, and its surface texture, shape, and any projections or pores form the primary morphological characters distinguishing species from one another. C. granulatus has been documented from Norwegian and Swedish freshwater bodies, consistent with the strong Scandinavian research tradition in chrysophyte taxonomy. Scandinavian oligotrophic and mesotrophic lakes are important reservoirs of chrysophyte diversity, harboring numerous species of Chrysococcus, Chromulina, Ochromonas, and related genera. Records from Brazil and Denmark extend the known distribution of C. granulatus, suggesting cosmopolitan or at least widespread dispersal capability through passive transport mechanisms such as wind, waterfowl, and hydrological connectivity. The species is a golden-brown phytoplankton organism with chlorophylls a and c and fucoxanthin carotenoids, enabling photosynthesis in the limnetic zone. Like other Chrysococcus species, C. granulatus may supplement photosynthesis with phagotrophic uptake of bacteria. It has not been assessed under IUCN criteria and carries a conservation status of Not Evaluated. The species contributes to understanding freshwater chrysophyte taxonomy and biodiversity in Scandinavian aquatic ecosystems.