vs Common Water Rat

Chroococcus dispersus compared with Hydromys chrysogaster

Key Differences

• is Not Evaluated while Common Water Rat is Least Concern.

Taxonomic Classification

Rank		Common Water Rat
Kingdom	Bacteria (Bacteria)	Animalia (Animals)
Phylum	Cyanobacteria (Cyanobacteria)	Chordata (Chordates)
Class	Cyanobacteriia	Mammalia (Mammals)
Order	Cyanobacteriales	Rodentia (Rodents)
Family	Microcystaceae	Muridae (Mice & Rats)
Genus	Chroococcus	Hydromys
Species	Chroococcus dispersus	Hydromys chrysogaster

Conservation Status

NE — Not Evaluated

Common Water Rat

LC — Least Concern

Physical Characteristics

Attribute		Common Water Rat
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Asia and Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, Sweden, and Taiwan.

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Chroococcus dispersus is a species of cyanobacteria in the family Chroococcaceae, occurring in freshwater habitats including lakes, ponds, and slowly flowing waters. It belongs to a genus characterized by small, spherical cells grouped in pairs or quartets within a diffuse, hyaline sheath. The specific epithet dispersus suggests a tendency for cells or colonies to be loosely organized or widely distributed. Cyanobacteria in the genus Chroococcus are typical components of the plankton and periphyton of oligotrophic to mesotrophic freshwater bodies in temperate and boreal regions. They are photosynthetic, using sunlight and dissolved carbon dioxide to produce organic matter, and contribute to primary productivity in aquatic ecosystems. Some Chroococcus species can also fix atmospheric nitrogen under nitrogen-limited conditions, though this trait is more pronounced in filamentous cyanobacterial genera. Chroococcus dispersus has been identified from European freshwater systems and is representative of the diverse microfloral communities found in clean to moderately enriched freshwaters. It is not assessed by the IUCN and has no known economic significance, representing one of many microscopic components of aquatic biodiversity.

Common Water Rat

<em>Hydromys chrysogaster</em>, commonly known as the common water rat or rakali, is a semi-aquatic rodent in the family Muridae, native to Australia and New Guinea. It is classified as Least Concern by the IUCN, reflecting its relatively stable population across a broad range of freshwater and estuarine habitats on the Australian continent and associated islands. The species typically inhabits the banks of rivers, lakes, wetlands, and estuaries, where it constructs burrows in streambanks. It is highly adapted for an aquatic lifestyle, with partially webbed hind feet, a flattened head, and a dense waterproof coat. <em>Hydromys chrysogaster</em> is a carnivore, typically feeding on fish, crustaceans, mussels, frogs, and aquatic invertebrates, which it often carries to elevated feeding platforms to consume. The species is nocturnal and crepuscular, most active during early morning and evening hours near the water's edge. Biological traits including average lifespan, body length, and weight remain poorly documented in standardized databases, though adults are generally robust for a rodent, reportedly reaching body lengths of 20–35 cm excluding the tail. Geographic range details for this particular record remain incompletely documented in available data sources. Ecologically, the common water rat is an important apex predator in small-scale freshwater food webs and serves as an indicator species for wetland health in Australian riparian systems.