vs

Coelosphaerium confertum compared with Coelosphaerium subarcticum

Taxonomic Classification

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

Found in Denmark.

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Coelosphaerium confertum is a colonial planktonic cyanobacterium in the family Merismopediaceae, distinguished from related species by the relatively compact arrangement of cells within its gelatinous colonial matrix. Like other Coelosphaerium species, it forms roughly spherical mucilaginous colonies in which cells are positioned near the colony periphery. The genus belongs to the order Chroococcales and is characteristic of temperate freshwater habitats including lakes, ponds, and slow-moving rivers with moderate to high nutrient levels. Coelosphaerium confertum has been recorded from freshwater bodies in Denmark and other northern European countries, where it occurs as part of the phytoplankton assemblage during summer and early autumn months when temperatures are sufficient to sustain its growth. Cyanobacteria of this type are primary producers that fix atmospheric carbon and contribute to the base of aquatic food webs, supporting zooplankton and higher trophic levels. Under conditions of elevated phosphorus and nitrogen from agricultural runoff and wastewater, bloom-forming cyanobacteria can proliferate and alter the ecological character of water bodies. While Coelosphaerium confertum is not typically identified as a toxic bloom-former, its ecological role in nutrient cycling and as part of broader cyanobacterial assemblages is significant. No formal IUCN evaluation has been conducted.

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.