Coastal Flat-body vs Common Quaking Grass

Agonopterix yeatiana compared with Briza media

Key Differences

Coastal Flat-body is Near Threatened while Common Quaking Grass is Vulnerable.

Taxonomic Classification

Rank	Coastal Flat-body	Common Quaking Grass
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	Briza
Species	Agonopterix yeatiana	Briza media

Conservation Status

Coastal Flat-body

NT — Near Threatened

Common Quaking Grass

VU — Vulnerable

Physical Characteristics

Attribute	Coastal Flat-body	Common Quaking Grass
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 Quaking Grass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, temperate grasslands and steppes, and flooded grasslands and savannas, among 6 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Japan), Europe (7 countries), North America (Canada, United States), and South America (Argentina). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

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 Quaking Grass

The Common Quaking Grass, <em>Briza media</em>, is a perennial grass in the family Poaceae, native to Europe and parts of Asia and introduced to North America and South America. It is a characteristic species of ancient, species-rich calcareous grasslands, meadows, and chalk downlands, where it typically grows in well-drained, nutrient-poor soils in full sun. The species is easily recognized by its heart-shaped, flattened spikelets that hang on delicate, hair-like stalks and tremble in the slightest breeze, producing the distinctive quaking motion that gives the genus its common name. The spikelets are typically pale green when immature, turning golden-brown as they ripen, and the whole inflorescence is highly ornamental. <em>Briza media</em> is an important component of calcareous grassland communities, providing structure and seed resources for invertebrates and birds. It is sensitive to agricultural improvement and is often used as an indicator of long-undisturbed grasslands. The species is assessed as Vulnerable on the IUCN Red List, reflecting declines linked to habitat loss, agricultural intensification, and conversion of traditional grasslands. Biological traits such as average lifespan, body size, and specific dietary preferences remain poorly documented for this species.