Bolivian red howler vs Coastal Silver-stiletto

Alouatta sara compared with Acrosathe annulata

Key Differences

• Bolivian red howler is Near Threatened while Coastal Silver-stiletto is Least Concern.

Taxonomic Classification

Rank	Bolivian red howler	Coastal Silver-stiletto
Kingdom same	Animalia (animal)	Animalia (animal)
Phylum	Chordata (Chordates)	Arthropoda (arthropodes)
Class	Mammalia (mammifères)	Insecta (insecte)
Order	Primates (Primates)	Diptera (Diptera)
Family	Atelidae	Therevidae
Genus	Alouatta	Acrosathe
Species	Alouatta sara	Acrosathe annulata

Evolutionary Relationship

Bolivian red howler and Coastal Silver-stiletto share a common ancestor at the Kingdom level: Animalia. (animal)

Conservation Status

Bolivian red howler

NT — Near Threatened

Coastal Silver-stiletto

LC — Least Concern

Physical Characteristics

Attribute	Bolivian red howler	Coastal Silver-stiletto
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Bolivian red howler

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Bolivian red howler

The Bolivian red howler (Alouatta sara) is a species in the genus Alouatta. It is currently classified as Near Threatened on the IUCN Red List. Typically found in diverse terrestrial and aquatic ecosystems.

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.