common sea hare vs eccentric grass snail

Aplysia punctata compared with Vallonia excentrica

Key Differences

• common sea hare is Least Concern while eccentric grass snail is Near Threatened.

Taxonomic Classification

Rank	common sea hare	eccentric grass snail
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Mollusca (Mollusks)	Mollusca (Mollusks)
Class same	Gastropoda (Gastropoda)	Gastropoda (Gastropoda)
Order	Aplysiida (Aplysiida)	Stylommatophora (Stylommatophora)
Family	Aplysiidae	Valloniidae
Genus	Aplysia	Vallonia
Species	Aplysia punctata	Vallonia excentrica

Evolutionary Relationship

common sea hare and eccentric grass snail share a common ancestor at the Class level: Gastropoda. (Gastropoda)

Conservation Status

common sea hare

LC — Least Concern

eccentric grass snail

NT — Near Threatened

Physical Characteristics

Attribute	common sea hare	eccentric grass snail
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.

eccentric grass snail

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, tundra, and tropical and subtropical moist broadleaf forests, among 5 distinct biome types spanning the Australasia and Oceanian and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Israel), Europe (9 countries), North America (Mexico, United States), and Oceania and the Pacific (New Zealand). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

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.

Shared Countries

Both species can be found in 4 countries:

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