Common Brassy Ringlet vs Common Water Rat

Erebia cassioides compared with Hydromys chrysogaster

Taxonomic Classification

Rank	Common Brassy Ringlet	Common Water Rat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Insecta (Insects)	Mammalia (Mammals)
Order	Lepidoptera (Butterflies & Moths)	Rodentia (Rodents)
Family	Nymphalidae (Brush-footed Butterflies)	Muridae (Mice & Rats)
Genus	Erebia	Hydromys
Species	Erebia cassioides	Hydromys chrysogaster

Evolutionary Relationship

Common Brassy Ringlet and Common Water Rat share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Brassy Ringlet

LC — Least Concern

Common Water Rat

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Common Brassy Ringlet

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Austria, Bosnia and Herzegovina, Bulgaria, and Italy.

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Common Brassy Ringlet

The common brassy ringlet (<em>Erebia cassioides</em>) is a butterfly species endemic to high-altitude mountain environments of central and southern Europe, with documented occurrences in Austria, Bosnia and Herzegovina, Bulgaria, and Italy. This species typically inhabits all terrestrial and freshwater environments within its alpine range, favoring subalpine and alpine grasslands at elevations often exceeding 1,500 meters. It is classified as Least Concern on the IUCN Red List, reflecting a currently stable population status. As a member of the family Nymphalidae, the common brassy ringlet often feeds on grasses and sedges during its larval stage, while adult butterflies are typically found nectaring on alpine flowers. The species is often associated with calcareous grasslands and rocky slopes, where it can be seen flying in warm, sunny conditions during the summer months. Biological traits of this species remain poorly documented in the scientific literature.

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.