Arctic lemming vs Clustered Stonewort

Dicrostonyx torquatus compared with Tolypella glomerata

Key Differences

Arctic lemming is Least Concern while Clustered Stonewort is Vulnerable.

Taxonomic Classification

Rank	Arctic lemming	Clustered Stonewort
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Chordata (Chordates)	Charophyta (Charophyta)
Class	Mammalia (Mammals)	Charophyceae (Charophyceae)
Order	Rodentia (Rodents)	Charales (Charales)
Family	Cricetidae	Characeae
Genus	Dicrostonyx	Tolypella
Species	Dicrostonyx torquatus	Tolypella glomerata

Conservation Status

Arctic lemming

LC — Least Concern

Clustered Stonewort

VU — Vulnerable

Physical Characteristics

Attribute	Arctic lemming	Clustered Stonewort
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Arctic lemming

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Clustered Stonewort

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Arctic lemming

The Arctic lemming (Dicrostonyx torquatus) is a species in the genus Dicrostonyx. It is currently classified as Least Concern on the IUCN Red List. Typically found in diverse terrestrial and aquatic ecosystems.

Clustered Stonewort

Tolypella glomerata, the clustered stonewort, is a charophyte alga in the family Characeae, found in calcareous, nutrient-poor freshwater habitats including lakes, ponds, ditches, and slow-flowing water in northwestern and northern Europe. Charophytes are macroscopic green algae with a distinctive whorl-like arrangement of branches and a complex, plant-like structure that distinguishes them from other algae. T. glomerata is encrusted with calcium carbonate deposits (hence 'stonewort'), giving it a pale, grey-green appearance and rough texture. The species colonizes clear, low-nutrient water over fine sediment or gravel substrates where competition from vascular plants is reduced by nutrient limitation. It is listed as Vulnerable by the IUCN, reflecting significant declines driven by eutrophication (nutrient enrichment from agriculture and sewage), which promotes the growth of vascular plants and phytoplankton that shade out stoneworts. Drainage, water abstraction, and peat cutting also threaten its habitats. Charophyte diversity has declined substantially across lowland Europe and North America over the past century, with many species becoming locally extinct from sites they once colonized.