Coastal Silver-stiletto vs Common Fleabane

Acrosathe annulata compared with Erigeron philadelphicus

Key Differences

Coastal Silver-stiletto is Least Concern while Common Fleabane is Not Evaluated.

Taxonomic Classification

Rank	Coastal Silver-stiletto	Common Fleabane
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Magnoliopsida (Dicots)
Order	Diptera (Diptera)	Asterales (Daisies & Sunflowers)
Family	Therevidae	Asteraceae (Daisy Family)
Genus	Acrosathe	Erigeron
Species	Acrosathe annulata	Erigeron philadelphicus

Conservation Status

Coastal Silver-stiletto

LC — Least Concern

Common Fleabane

NE — Not Evaluated

Physical Characteristics

Attribute	Coastal Silver-stiletto	Common Fleabane
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Common Fleabane

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Widely distributed across Asia (China, Japan), Europe (8 countries), and North America (United States).

Coastal Silver-stiletto

Coastal silver stiletto (Acrosathe annulata) is a slender robber fly in the family Therevidae, native to northwestern Europe, including the United Kingdom, France, the Netherlands, Belgium, and Scandinavia. Adults are found on coastal sand dunes and sandy heathland, where they perch on bare sand to ambush small flying insects. Stiletto flies in the family Therevidae are characterised by a slender body, long pointed abdomen, and predatory habits; adults prey on a variety of small dipterans and other flying insects during warm, sunny periods. Larvae develop in sandy soil, where they are also predatory, feeding on other invertebrate larvae. Acrosathe annulata is a habitat specialist restricted to open, sandy coastal habitats with sparse vegetation—environments that have declined substantially across northwestern Europe due to dune stabilisation, recreational disturbance, and the cessation of traditional dune management. The IUCN lists it as Least Concern, though regional conservation bodies in the United Kingdom have flagged population declines. It is considered an indicator of high-quality coastal sand dune habitats and is monitored through national invertebrate surveys.

Common Fleabane

<em>Erigeron philadelphicus</em> is an annual or biennial herbaceous plant in the family Asteraceae, order Asterales, commonly known as Philadelphia fleabane or common fleabane. This species produces numerous small, pale pink to white daisy-like flowerheads with many narrow ray florets surrounding a yellow disc center. <em>Erigeron philadelphicus</em> has a broad distribution spanning Asia, Europe, and North America, where it is native and widely naturalized. It typically grows in moist, disturbed habitats such as meadows, roadsides, stream banks, and open woodland, tolerating a wide range of soil types and moisture conditions. The plant is generally considered a common weed in many parts of its range and is notable for its prolific seed production, which facilitates rapid colonization of disturbed ground. Despite its weedy tendencies, the species provides valuable nectar resources for pollinators. Biological traits of this species remain poorly documented in the scientific literature.