vs

Coelosphaerium aerugineum compared with Coelosphaerium subarcticum

Taxonomic Classification

Rank
Kingdom same	Bacteria (Bacteria)	Bacteria (Bacteria)
Phylum same	Cyanobacteria (Siyanobakteri)	Cyanobacteria (Siyanobakteri)
Class same	Cyanobacteriia	Cyanobacteriia
Order same	Cyanobacteriales	Cyanobacteriales
Family same	Microcystaceae	Microcystaceae
Genus same	Coelosphaerium	Coelosphaerium
Species	Coelosphaerium aerugineum	Coelosphaerium subarcticum

Evolutionary Relationship

and share a common ancestor at the Genus level: Coelosphaerium.

Conservation Status

NE — Not Evaluated

NE — Not Evaluated

Physical Characteristics

Attribute
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Coelosphaerium aerugineum is a colonial planktonic cyanobacterium in the family Merismopediaceae, forming spherical to irregularly shaped gelatinous colonies in which individual cells are arranged in a peripheral layer surrounding a central mucilaginous matrix. Like other members of the genus, C. aerugineum is found in freshwater lakes, ponds, and slow-flowing waters of the temperate zone, including Scandinavia. Cyanobacteria are among the oldest life forms on Earth, contributing to oxygen evolution in ancient oceans, and continue to play fundamental roles in modern aquatic biogeochemistry through nitrogen fixation and primary production. Coelosphaerium species can form blooms under nutrient-enriched eutrophic conditions, although they are generally less notorious for bloom formation than genera such as Microcystis or Dolichospermum. The spherical colonial architecture provides some protection against grazing by zooplankton, while the cells contain gas vesicles that assist in vertical positioning within the water column. Distribution of Coelosphaerium aerugineum spans temperate freshwater habitats across Europe, including northern countries such as Norway and Sweden, where it occurs in lakes and reservoirs during warmer months. No formal conservation assessment has been undertaken for this species, as freshwater cyanobacteria at this taxonomic level are generally not evaluated by the IUCN.

Coelosphaerium subarcticum is a colonial planktonic cyanobacterium in the family Merismopediaceae, as its epithet suggests, with distribution records concentrated in subarctic and boreal freshwater environments of Scandinavia, specifically Norway and Sweden. The species forms spherical mucilaginous colonies with peripheral cell arrangement typical of the genus, and its adaptation to cold water temperatures distinguishes it ecologically from congeners that prefer warmer, more eutrophic conditions. Subarctic lakes and ponds are characterised by low temperatures, ice cover for much of the year, and typically oligotrophic to mesotrophic conditions with relatively low nutrient levels. In such settings, cyanobacteria including Coelosphaerium subarcticum contribute to primary production during the ice-free summer season when available light and temperatures support photosynthesis. Gas vesicles in the cells enable buoyancy regulation, allowing colonies to rise toward surface light layers during calm conditions. Arctic and subarctic freshwater ecosystems are among the environments most sensitive to climate-driven changes, with warming temperatures extending the growing season, altering ice regimes, and potentially enabling southerly species to expand northward while cold-adapted taxa face range contraction. No formal IUCN conservation evaluation has been conducted for this species, as is typical for planktonic microorganisms at this taxonomic level.

Shared Countries

Both species can be found in 2 countries:

🇳🇴 Norway 🇸🇪 Sweden