Bracken vs Coastal Silver-stiletto

Pteridium aquilinum compared with Acrosathe annulata

Taxonomic Classification

Rank	Bracken	Coastal Silver-stiletto
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Tracheophyta	Arthropoda (Arthropods)
Class	Polypodiopsida (Polypodiopsida)	Insecta (Insects)
Order	Polypodiales (Polypodiales)	Diptera (Diptera)
Family	Dennstaedtiaceae	Therevidae
Genus	Pteridium	Acrosathe
Species	Pteridium aquilinum	Acrosathe annulata

Conservation Status

Bracken

LC — Least Concern

Coastal Silver-stiletto

LC — Least Concern

Physical Characteristics

Attribute	Bracken	Coastal Silver-stiletto
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Bracken

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and flooded grasslands and savannas, among 9 distinct biome types spanning the Afrotropic and Neotropic and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (6 countries), Asia (Iran, Turkey), Europe (6 countries), North America (4 countries), Oceania and the Pacific (Australia), and South America (4 countries).

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Bracken

The Bracken (Pteridium aquilinum) is a species in the genus Pteridium. It is currently classified as Least Concern on the IUCN Red List. Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and flooded grasslands and savannas, among 9 distinct biome types spanning the Afrotropic and Ne

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.