Canadian beaver vs

Castor canadensis compared with Chrysosphaerella triangulata

Taxonomic Classification

Rank	Canadian beaver
Kingdom	Animalia (Animals)	Chromista (Chromista)
Phylum	Chordata (Chordates)	Ochrophyta (Ochrophyta)
Class	Mammalia (Mammals)	Chrysophyceae (Chrysophyceae)
Order	Rodentia (Rodents)	Ochromonadales (Ochromonadales)
Family	Castoridae (Beavers)	Paraphysomonadaceae
Genus	Castor (Beavers)	Chrysosphaerella
Species	Castor canadensis	Chrysosphaerella triangulata

Conservation Status

Canadian beaver

NE — Not Evaluated

Population: ~15.0M

Trend: Stable →

NE — Not Evaluated

Physical Characteristics

Attribute	Canadian beaver
Diet	Herbivore	—
Average Lifespan	15 years	—
Average Length	1.0 m	—
Average Weight	25.0 kg	—

Habitat & Geographic Range

Canadian beaver

Habitat

Typically found in grasslands, forests, and vegetated habitats.

Range

Widely distributed across Europe (15 countries), North America (United States), and South America (Argentina, Chile).

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Canadian beaver

The largest rodent in North America, Canadian beavers weigh up to 32 kg and are master ecosystem engineers inhabiting rivers, lakes, and wetlands across Canada and the northern United States. By felling trees and constructing dams up to hundreds of meters long, beavers create ponds that provide habitat for hundreds of species. Their lodges and canals transform entire watersheds. Once nearly hunted to extinction for their fur, beaver populations have recovered strongly.

Chrysosphaerella triangulata is a colonial freshwater chrysophyte microalga in the genus Chrysosphaerella, class Chrysophyceae, order Chromulinales. Chrysosphaerella species form spherical free-floating colonies of golden-brown cells embedded in a gelatinous matrix, with individual cells bearing elongated siliceous scales that project outward from the colony surface. The species epithet triangulata — triangular — refers to the triangular cross-section or profile of the siliceous scales on the cell surface, which distinguishes this species from C. annulata, which has annular ring structures on its scales, and from other congeners with different scale geometries. Siliceous scale morphology examined under scanning electron microscopy is the primary diagnostic character for Chrysosphaerella species identification. C. triangulata has been recorded from Norwegian and Swedish freshwater habitats, part of the documented chrysophyte flora of boreal and subarctic Scandinavian lakes. These environments are characterized by cold, clear, nutrient-poor water and seasonal ice cover, creating conditions favorable for chrysophyte diversity including colonial forms like Chrysosphaerella. The colonies inhabit the photic zone of the water column, photosynthesizing with chlorophylls a and c and carotenoid accessory pigments. Chrysosphaerella scales deposited in lake sediments serve as paleolimnological indicators. C. triangulata has not been formally evaluated under IUCN criteria and is listed as Not Evaluated. It contributes to documentation of the rich chrysophyte diversity in Scandinavian freshwater systems.