vs Common Water Rat

Chroomonas acuta compared with Hydromys chrysogaster

Key Differences

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

Taxonomic Classification

Rank		Common Water Rat
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Cryptophyta	Chordata (Chordates)
Class	Cryptophyceae (Cryptophyceae)	Mammalia (Mammals)
Order	Pyrenomonadales (Pyrenomonadales)	Rodentia (Rodents)
Family	Chroomonadaceae	Muridae (Mice & Rats)
Genus	Chroomonas	Hydromys
Species	Chroomonas acuta	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.

Chroomonas acuta is a species of cryptophyte alga in the family Chroomonadaceae, found in freshwater and brackish aquatic environments. Cryptophytes are biflagellate, unicellular algae characterized by the presence of a unique organelle called the nucleomorph — a remnant nucleus from a secondary endosymbiotic event in which an ancestral flagellate engulfed a red alga. This evolutionary heritage is reflected in the distinctive combination of pigments in the plastid, including chlorophyll a, chlorophyll c, and phycobiliproteins such as phycoerythrin and phycocyanin, which give cryptophytes their often blue-green to red-brown color. Chroomonas species are small flagellates that swim using two unequal flagella arising from a ventral groove. They are important members of freshwater phytoplankton communities, particularly in the cold-water picoplankton. Chroomonas acuta has a more pointed or acute cell shape compared to some related species, as indicated by its epithet. The species has been documented from European freshwater habitats. Cryptophytes contribute to primary production in freshwater and marine ecosystems and are a significant food source for heterotrophic protists and filter-feeding zooplankton. The species has not been assessed by the IUCN.

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.