Coastal Silver-stiletto vs common poisonrope

Acrosathe annulata compared with Strophanthus speciosus

Taxonomic Classification

Rank	Coastal Silver-stiletto	common poisonrope
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Magnoliopsida (Dicots)
Order	Diptera (Diptera)	Gentianales (Gentianales)
Family	Therevidae	Apocynaceae
Genus	Acrosathe	Strophanthus
Species	Acrosathe annulata	Strophanthus speciosus

Conservation Status

Coastal Silver-stiletto

LC — Least Concern

common poisonrope

LC — Least Concern

Physical Characteristics

Attribute	Coastal Silver-stiletto	common poisonrope
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 poisonrope

Habitat

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

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 poisonrope

<em>Strophanthus speciosus</em>, the common poisonrope, is a woody climbing vine in the family Apocynaceae, native to Africa. It is characterised by striking flowers with long, strap-like petal extensions or "tails" that dangle from the corolla, attracting specialist pollinators. Like other members of the genus Strophanthus, it produces toxic cardiac glycosides, particularly strophanthin, in its seeds, which have been used historically in the preparation of arrow poisons across various African cultures and have also been investigated for medicinal applications in cardiology. The species typically grows in forest margins, woodland edges, riverine scrub, and disturbed vegetation across its African range, where it uses supporting vegetation to climb towards the forest canopy. <em>Strophanthus speciosus</em> is assessed as Least Concern on the IUCN Red List, reflecting an adequate distribution across suitable African habitats. Detailed country-level distribution data are not fully compiled. Biological traits such as average vine lifespan, stem dimensions, body mass, and comprehensive dietary or physiological data remain poorly documented in the scientific literature. The species is of historical and ongoing pharmacological interest due to its cardenolide chemistry.