vs Common Water Rat

Chroococcus submarinus 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 submarinus	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 Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Chroococcus submarinus is a species of cyanobacteria in the family Chroococcaceae, documented from saline and brackish aquatic environments. The specific epithet submarinus indicates an association with marine or nearshore saline habitats, distinguishing this species from the many Chroococcus species found exclusively in freshwater. Cyanobacteria are notably tolerant of a wide range of salinities, and the genus Chroococcus includes species from freshwater, brackish, marine, and hypersaline environments. In marine and coastal habitats, cyanobacteria contribute significantly to nitrogen fixation, particularly in oligotrophic tropical and subtropical seas where they can fix atmospheric nitrogen into biologically available forms, subsidizing productivity. Chroococcus submarinus, like other members of the genus, consists of spherical cells occurring in pairs or small groups within gelatinous sheaths. Marine cyanobacteria are important components of coastal biofilms on rocky shores, seagrass meadows, and other benthic habitats. The species has been recorded from European coastal and semi-saline environments. As a prokaryotic microorganism, it has not been assessed under IUCN criteria, and detailed ecological studies specific to this species remain limited.

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.