Coastal Flat-body vs Running mountaingrass

Agonopterix yeatiana compared with Oplismenus compositus

Key Differences

• Coastal Flat-body is Near Threatened while Running mountaingrass is Least Concern.

Taxonomic Classification

Rank	Coastal Flat-body	Running mountaingrass
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Liliopsida (Monocots)
Order	Lepidoptera (Butterflies & Moths)	Poales (Grasses)
Family	Depressariidae	Poaceae (Grass Family)
Genus	Agonopterix	Oplismenus
Species	Agonopterix yeatiana	Oplismenus compositus

Conservation Status

Coastal Flat-body

NT — Near Threatened

Running mountaingrass

LC — Least Concern

Physical Characteristics

Attribute	Coastal Flat-body	Running mountaingrass
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.

Running mountaingrass

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Asia (Indonesia, Taiwan), Europe (France, United Kingdom), North America (Guatemala, Honduras, United States), Oceania and the Pacific (9 countries), and South America (Colombia).

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.