Brook Floater vs

Alasmidonta varicosa compared with Chroococcus minutus

Key Differences

• Brook Floater is Vulnerable while is Not Evaluated.

Taxonomic Classification

Rank	Brook Floater
Kingdom	Animalia (Animals)	Bacteria (Bacteria)
Phylum	Mollusca (Mollusks)	Cyanobacteria (Cyanobacteria)
Class	Bivalvia (Bivalvia)	Cyanobacteriia
Order	Unionida (Unionida)	Cyanobacteriales
Family	Unionidae	Microcystaceae
Genus	Alasmidonta	Chroococcus
Species	Alasmidonta varicosa	Chroococcus minutus

Conservation Status

Brook Floater

VU — Vulnerable

NE — Not Evaluated

Physical Characteristics

Attribute	Brook Floater
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brook Floater

Habitat

Native to North America, inhabiting ecosystems characteristic of the region.

Range

Found in United States. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

Brook Floater

The Brook Floater (Alasmidonta varicosa) is a species in the genus Alasmidonta. It is currently classified as Vulnerable on the IUCN Red List. Native to North America, inhabiting ecosystems characteristic of the region.

Chroococcus minutus is a cyanobacterium in the family Chroococcaceae, recognized as one of the smaller species in the genus. It is distributed in freshwater habitats across temperate regions, including Scandinavia and northern Europe, where it has been documented in taxonomic surveys of freshwater algae and cyanobacteria. Chroococcus species in general are characterized by their simple morphology — spherical or hemispherical cells, binary fission, and organization into pairs or tetrads within gelatinous sheaths. Chroococcus minutus occurs in the plankton and periphyton of lakes, ponds, and slowly flowing waters with low to moderate nutrient levels. Cyanobacteria of this type play roles in primary production and, in certain metabolically active strains, may contribute to nitrogen fixation in nitrogen-limited aquatic systems. The taxonomy of small-celled Chroococcus species remains challenging, with morphological overlap between species and significant variation in cell size related to environmental conditions and growth stage. Recent molecular studies have revealed that morphologically defined genera such as Chroococcus represent multiple phylogenetic lineages, indicating likely future taxonomic rearrangements. The species is not assessed by the IUCN.