Common Nut Clam vs Grizzled Colilargo

Nuculana pernula compared with Oligoryzomys griseolus

Key Differences

• Common Nut Clam is Vulnerable while Grizzled Colilargo is Least Concern.

Taxonomic Classification

Rank	Common Nut Clam	Grizzled Colilargo
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (Mollusks)	Chordata (Chordates)
Class	Bivalvia (Bivalvia)	Mammalia (Mammals)
Order	Nuculanida (Nuculanida)	Rodentia (Rodents)
Family	Nuculanidae	Cricetidae
Genus	Nuculana	Oligoryzomys
Species	Nuculana pernula	Oligoryzomys griseolus

Evolutionary Relationship

Common Nut Clam and Grizzled Colilargo share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Nut Clam

VU — Vulnerable

Grizzled Colilargo

LC — Least Concern

Physical Characteristics

Attribute	Common Nut Clam	Grizzled Colilargo
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic 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.

Grizzled Colilargo

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Distributed across Colombia and Venezuela.

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.