brittlestar vs Common Tern

Amphiura filiformis compared with Sterna hirundo

Key Differences

• brittlestar is Least Concern while Common Tern is Endangered.

Taxonomic Classification

Rank	brittlestar	Common Tern
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Echinodermata (Echinoderms)	Chordata (Chordates)
Class	Ophiuroidea (Ophiuroidea)	Aves (Birds)
Order	Amphilepidida (Amphilepidida)	Charadriiformes (Charadriiformes)
Family	Amphiuridae	Laridae
Genus	Amphiura	Sterna
Species	Amphiura filiformis	Sterna hirundo

Evolutionary Relationship

brittlestar and Common Tern share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

brittlestar

LC — Least Concern

Common Tern

EN — Endangered

Physical Characteristics

Attribute	brittlestar	Common Tern
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

brittlestar

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

Common Tern

Habitat

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

Range

Widely distributed across Europe (7 countries), North America (United States), and South America (Colombia, Ecuador, Venezuela). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

brittlestar

The Brittlestar (Amphiura filiformis) is a species in the genus Amphiura. It is currently classified as Least Concern on the IUCN Red List. Native to Europe, inhabiting ecosystems characteristic of the region.

Common Tern

Common Tern (Sterna hirundo) is classified as Endangered (EN) on the IUCN Red List. At high risk of extinction in the wild, with significant population decline and ongoing threats to survival.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden