Common Pellia vs common sea hare

Pellia epiphylla compared with Aplysia punctata

Key Differences

• Common Pellia is Vulnerable while common sea hare is Least Concern.

Taxonomic Classification

Rank	Common Pellia	common sea hare
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Marchantiophyta (liverwort)	Mollusca (Mollusks)
Class	Jungermanniopsida (Jungermanniopsida)	Gastropoda (Gastropoda)
Order	Pelliales (Pelliales)	Aplysiida (Aplysiida)
Family	Pelliaceae	Aplysiidae
Genus	Pellia	Aplysia
Species	Pellia epiphylla	Aplysia punctata

Conservation Status

Common Pellia

VU — Vulnerable

common sea hare

LC — Least Concern

Physical Characteristics

Attribute	Common Pellia	common sea hare
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Pellia

Habitat

Native to Asia and Europe and North America, inhabiting ecosystems characteristic of the region.

Range

Widely distributed across Asia (Taiwan), Europe (7 countries), and North America (United States). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

common sea hare

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Common Pellia

<em>Pellia epiphylla</em>, known as the common pellia, is a thallose liverwort in the family Pelliaceae and one of the most frequently encountered bryophytes in temperate regions. It grows in dense, dark-green mats typically found along stream banks, wet rock faces, moist woodland floors, and other persistently damp habitats where it can absorb water directly through its undifferentiated thallus. The species is distributed across Europe, including Belgium, Denmark, Luxembourg, Norway, and Portugal, as well as parts of Asia including Taiwan and North America including the United States, reflecting a broadly circumboreal range. <em>Pellia epiphylla</em> reproduces both sexually, producing distinctive stalked spore capsules in spring, and vegetatively through fragmentation. It is currently assessed as Vulnerable on the IUCN Red List, indicating that populations face moderate risk due to habitat loss and degradation associated with wetland drainage, water pollution, and land-use change. Biological traits such as average lifespan, thallus dimensions, and detailed ecological requirements remain poorly documented compared to vascular plants. The species is ecologically important as a pioneer on disturbed moist soils and contributes to moisture retention in riparian ecosystems.

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