Big eye thresher shark vs Common Nut Clam

Alopias superciliosus compared with Nuculana pernula

Taxonomic Classification

Rank	Big eye thresher shark	Common Nut Clam
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Chondrichthyes (Cartilaginous Fish)	Bivalvia (Bivalvia)
Order	Lamniformes (Mackerel Sharks)	Nuculanida (Nuculanida)
Family	Alopiidae	Nuculanidae
Genus	Alopias	Nuculana
Species	Alopias superciliosus	Nuculana pernula

Evolutionary Relationship

Big eye thresher shark and Common Nut Clam share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Big eye thresher shark

VU — Vulnerable

Common Nut Clam

VU — Vulnerable

Physical Characteristics

Attribute	Big eye thresher shark	Common Nut Clam
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Big eye thresher shark

Habitat

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

Range

Distributed across Chile, Colombia, Portugal, Taiwan, and Venezuela. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Nut Clam

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Big eye thresher shark

The Big eye thresher shark (Alopias superciliosus) is a species in the genus Alopias. It is currently classified as Vulnerable on the IUCN Red List. Typically found in marine environments from coastal waters to deep ocean.

Common Nut Clam

<em>Nuculana pernula</em>, sometimes referred to as a nut clam, is a small marine bivalve mollusk in the family Nuculanidae, part of the subclass Protobranchia. Like other protobranchs, <em>Nuculana pernula</em> is a deposit feeder that typically burrows into fine-grained marine sediments, using its palp proboscides to gather organic detritus and microorganisms from surface sediment layers. It typically inhabits subtidal and deep-water soft-bottom habitats along cold-temperate and boreal Atlantic coasts, with documented occurrences in Denmark, Norway, and Sweden. The species is currently assessed as Vulnerable by the IUCN, indicating that it faces a higher level of extinction risk than related species, potentially reflecting sensitivity to habitat degradation, bottom trawling disturbance, and shifts in sediment quality. Biological traits such as lifespan, body size, and diet remain poorly documented at a standardized population level for this species. <em>Nuculana pernula</em> contributes to benthic ecosystem function through sediment bioturbation and organic matter processing, and its Vulnerable status highlights the importance of protecting deep-sea and subtidal soft-sediment habitats from physical disturbance.