Clawed enope squid vs Common Nut Clam

Abraliopsis felis compared with Nuculana pernula

Key Differences

• Clawed enope squid is Least Concern while Common Nut Clam is Vulnerable.

Taxonomic Classification

Rank	Clawed enope squid	Common Nut Clam
Kingdom same	Animalia (动物界)	Animalia (动物界)
Phylum same	Mollusca (软体动物门)	Mollusca (软体动物门)
Class	Cephalopoda (头足纲)	Bivalvia (双壳纲)
Order	Oegopsida (开眼目)	Nuculanida (吻状蛤目)
Family	Enoploteuthidae	Nuculanidae
Genus	Abraliopsis	Nuculana
Species	Abraliopsis felis	Nuculana pernula

Evolutionary Relationship

Clawed enope squid and Common Nut Clam share a common ancestor at the Phylum level: Mollusca. (软体动物门)

Conservation Status

Clawed enope squid

LC — Least Concern

Common Nut Clam

VU — Vulnerable

Physical Characteristics

Attribute	Clawed enope squid	Common Nut Clam
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Clawed enope squid

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.

Clawed enope squid

The Clawed Enope Squid, Ancistrocheirus lesueurii, is a medium-sized oceanic squid in the family Ancistrocheiridae found in mesopelagic and bathypelagic zones of the Atlantic, Pacific, and Indian Oceans. It is the sole species in its family, representing a phylogenetically isolated lineage of deep-sea squids. The species is characterized by powerful, hook-bearing tentacles used to capture prey, an adaptation reflected in its common name. The mantle is muscular and elongated, bearing lateral fins, and the arms bear suckers modified into sharp hooks in adults. Ancistrocheirus lesueurii performs diel vertical migrations, ascending toward the surface at night and retreating to deeper waters during daylight hours. It is a voracious predator of fish and other squids, and is in turn preyed upon by sperm whales, large pelagic fishes, and sharks. Bioluminescent photophores are present on the body and arms, likely functioning in counterillumination or signaling. As a mesopelagic species distributed throughout major ocean basins, the Clawed Enope Squid contributes significantly to vertical carbon transport in marine ecosystems, processing organic material from surface waters and redistributing it at depth. Population status is unknown; the species has not been assessed by IUCN. It is occasionally recovered in the stomach contents of top predators and from deep-sea trawl surveys.

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.