brittlestar vs common Atlantic octopus

Amphiura filiformis compared with Octopus vulgaris

Key Differences

brittlestar is Least Concern while common Atlantic octopus is Not Evaluated.

Taxonomic Classification

Rank	brittlestar	common Atlantic octopus
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Echinodermata (Echinoderms)	Mollusca (Mollusks)
Class	Ophiuroidea (Ophiuroidea)	Cephalopoda (Cephalopods)
Order	Amphilepidida (Amphilepidida)	Octopoda (Octopuses)
Family	Amphiuridae	Octopodidae (Common Octopuses)
Genus	Amphiura	Octopus (Octopuses)
Species	Amphiura filiformis	Octopus vulgaris

Evolutionary Relationship

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

View Kingdom: Animalia

Conservation Status

brittlestar

LC — Least Concern

common Atlantic octopus

NE — Not Evaluated

Trend: Stable →

Physical Characteristics

Attribute	brittlestar	common Atlantic octopus
Diet	—	Carnivore
Average Lifespan	—	2 years
Average Length	—	60 cm
Average Weight	—	5.0 kg

Habitat & Geographic Range

brittlestar

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

common Atlantic octopus

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Distributed across Chile, Denmark, Norway, Portugal, and Sweden.

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 Atlantic octopus

One of the most studied invertebrates in neuroscience and behavioral biology, common octopuses inhabit rocky reefs and seafloors in tropical and temperate coastal waters globally. Highly intelligent with distributed nervous systems — two-thirds of their 500 million neurons reside in their arms — they demonstrate tool use, problem-solving, and individual personalities. Masters of camouflage, they change skin color and texture in milliseconds. They have three hearts, blue copper-based blood, and extremely short lifespans of 1–2 years.