common sea hare vs Large-Neck Clam

Aplysia punctata compared with Mya arenaria

Key Differences

• common sea hare is Least Concern while Large-Neck Clam is Vulnerable.

Taxonomic Classification

Rank	common sea hare	Large-Neck Clam
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Mollusca (Mollusks)	Mollusca (Mollusks)
Class	Gastropoda (Gastropoda)	Bivalvia (Bivalvia)
Order	Aplysiida (Aplysiida)	Myida (Myida)
Family	Aplysiidae	Myidae
Genus	Aplysia	Mya
Species	Aplysia punctata	Mya arenaria

Evolutionary Relationship

common sea hare and Large-Neck Clam share a common ancestor at the Phylum level: Mollusca. (Mollusks)

Conservation Status

common sea hare

LC — Least Concern

Large-Neck Clam

VU — Vulnerable

Physical Characteristics

Attribute	common sea hare	Large-Neck Clam
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

common sea hare

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Large-Neck Clam

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and temperate grasslands and steppes, among 5 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Georgia, Turkey), Europe (22 countries), and North America (Canada, United States). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

common sea hare

<em>Aplysia punctata</em>, the common sea hare, is a large opisthobranch sea slug in the family Aplysiidae, order Aplysiida, found in the northeastern Atlantic Ocean and Mediterranean Sea, with confirmed records from Denmark, Norway, Portugal, and Sweden. This species typically inhabits shallow subtidal and intertidal zones with abundant macroalgae, feeding primarily on red and green algae — a diet that influences the color of the defensive purple ink it secretes when threatened. <em>Aplysia punctata</em> is a simultaneous hermaphrodite, capable of acting as both male and female during mating, and often forms mating chains involving multiple individuals. It can reach considerable size among European opisthobranch species, though body dimensions vary considerably with age and feeding conditions. The species is classified as Least Concern by the IUCN, reflecting stable populations across its coastal range. Biological traits for this species remain poorly documented in the scientific literature, including precise average data on lifespan, body length, weight, and detailed seasonal dietary patterns, though its general herbivorous feeding on macroalgae is well established.

Large-Neck Clam

Large-Neck Clam (Mya arenaria) is classified as Vulnerable (VU) on the IUCN Red List. Facing a high risk of endangerment in the wild, with declining populations and increasing habitat pressure.

Shared Countries

Both species can be found in 4 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden