Coastal Flat-body vs Common Water Rat

Agonopterix yeatiana compared with Hydromys chrysogaster

Key Differences

• Coastal Flat-body is Near Threatened while Common Water Rat is Least Concern.

Taxonomic Classification

Rank	Coastal Flat-body	Common Water Rat
Kingdom same	Animalia (动物界)	Animalia (动物界)
Phylum	Arthropoda (节肢动物门)	Chordata (脊索动物门)
Class	Insecta (昆蟲綱)	Mammalia (哺乳動物)
Order	Lepidoptera (鱗翅目)	Rodentia (啮齿目)
Family	Depressariidae	Muridae (Mice & Rats)
Genus	Agonopterix	Hydromys
Species	Agonopterix yeatiana	Hydromys chrysogaster

Evolutionary Relationship

Coastal Flat-body and Common Water Rat share a common ancestor at the Kingdom level: Animalia. (动物界)

Conservation Status

Coastal Flat-body

NT — Near Threatened

Common Water Rat

LC — Least Concern

Physical Characteristics

Attribute	Coastal Flat-body	Common Water Rat
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coastal Flat-body

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, and Sweden. Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Coastal Flat-body

Agonopterix yeatiana, the coastal flat-body, is a small moth in the family Depressariidae native to coastal and calcareous grassland habitats across western and northern Europe, with records from Belgium, Denmark, and Sweden. Moths in the family Depressariidae, commonly called flat-body moths due to the depressed posture they adopt when resting with wings held flat against the surface, are associated predominantly with umbellifer plants of the family Apiaceae as larval hosts. Agonopterix yeatiana larvae feed on wild carrot (Daucus carota), wild parsnip (Pastinaca sativa), and related coastal and grassland Apiaceae species, inhabiting the open, often calcareous or sandy habitats where these plants grow. Adult moths have greyish-brown forewing with a distinctive pattern of spots and dashes and reach approximately 8–12 millimeters in wingspan. The species is classified as Near Threatened by the IUCN, reflecting declines associated with the loss of traditional hay meadow management, coastal grassland degradation, and scrub encroachment that eliminates the open, flower-rich grassland habitats supporting its host plants. Agricultural intensification has reduced wild umbellifer populations significantly across lowland Europe, reducing food resources for larvae of specialist moths like A. yeatiana.

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.