Coastal Silver-stiletto vs Common comfrey

Acrosathe annulata compared with Symphytum officinale

Taxonomic Classification

Rank	Coastal Silver-stiletto	Common comfrey
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Magnoliopsida (Dicots)
Order	Diptera (Diptera)	Boraginales (Boraginales)
Family	Therevidae	Boraginaceae
Genus	Acrosathe	Symphytum
Species	Acrosathe annulata	Symphytum officinale

Conservation Status

Coastal Silver-stiletto

LC — Least Concern

Common comfrey

LC — Least Concern

Physical Characteristics

Attribute	Coastal Silver-stiletto	Common comfrey
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 comfrey

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, temperate broadleaf and mixed forests, and temperate coniferous forests, among 6 distinct biome types spanning the Indomalayan and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (4 countries), Europe (9 countries), North America (Canada, United States), Oceania and the Pacific (Australia), and South America (Colombia, Peru).

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 comfrey

<em>Symphytum officinale</em>, commonly known as common comfrey, is a perennial herbaceous plant in the family Boraginaceae. It is native to Europe and parts of Asia and has been naturalized across North America, Oceania, and South America. Common comfrey typically grows in moist, nutrient-rich habitats including riverbanks, ditches, floodplain meadows, and woodland margins. The plant produces large, lance-shaped leaves covered in coarse hairs and bears drooping clusters of tubular flowers that range from pale purple to white. It has a long history of medicinal use, particularly for wound healing and bone repair, due to the presence of allantoin in its tissues. However, it also contains pyrrolizidine alkaloids that can be toxic in high doses. The species is assessed as Least Concern by the IUCN. Biological traits of this species remain poorly documented in the scientific literature.