Bonnet hammerhead vs Coastal Silver-stiletto

Sphyrna tiburo compared with Acrosathe annulata

Key Differences

• Bonnet hammerhead is Endangered while Coastal Silver-stiletto is Least Concern.

Taxonomic Classification

Rank	Bonnet hammerhead	Coastal Silver-stiletto
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Arthropoda (Arthropods)
Class	Chondrichthyes (Cartilaginous Fish)	Insecta (Insects)
Order	Carcharhiniformes (Ground Sharks)	Diptera (Diptera)
Family	Sphyrnidae (Hammerhead Sharks)	Therevidae
Genus	Sphyrna (Hammerhead Sharks)	Acrosathe
Species	Sphyrna tiburo	Acrosathe annulata

Evolutionary Relationship

Bonnet hammerhead and Coastal Silver-stiletto share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Bonnet hammerhead

EN — Endangered

Coastal Silver-stiletto

LC — Least Concern

Physical Characteristics

Attribute	Bonnet hammerhead	Coastal Silver-stiletto
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Bonnet hammerhead

Habitat

Typically found in marine environments from coastal waters to deep ocean.

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Bonnet hammerhead

The Bonnet hammerhead (Sphyrna tiburo) is a species in the genus Sphyrna. It is currently classified as Endangered on the IUCN Red List. Typically found in marine environments from coastal waters to deep ocean.

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.