Clustered Stonewort vs Pygmy three-toed sloth

Tolypella glomerata compared with Bradypus pygmaeus

Key Differences

Clustered Stonewort is Vulnerable while Pygmy three-toed sloth is Critically Endangered.

Taxonomic Classification

Rank	Clustered Stonewort	Pygmy three-toed sloth
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Charophyta (Charophyta)	Chordata (Chordates)
Class	Charophyceae (Charophyceae)	Mammalia (Mammals)
Order	Charales (Charales)	Pilosa (Sloths & Anteaters)
Family	Characeae	Bradypodidae (Three-toed Sloths)
Genus	Tolypella	Bradypus (Three-toed Sloths)
Species	Tolypella glomerata	Bradypus pygmaeus

Conservation Status

Clustered Stonewort

VU — Vulnerable

Pygmy three-toed sloth

CR — Critically Endangered

Physical Characteristics

Attribute	Clustered Stonewort	Pygmy three-toed sloth
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

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.

Pygmy three-toed sloth

Habitat

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.