Chocolate arion vs Dauphin A Bec Blanc

Arion rufus compared with Lagenorhynchus albirostris

Key Differences

• Chocolate arion is Vulnerable while Dauphin A Bec Blanc is Not Evaluated.

Taxonomic Classification

Rank	Chocolate arion	Dauphin A Bec Blanc
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (Mollusks)	Chordata (Chordates)
Class	Gastropoda (Gastropoda)	Mammalia (Mammals)
Order	Stylommatophora (Stylommatophora)	Cetacea (Whales & Dolphins)
Family	Arionidae	Delphinidae (Oceanic Dolphins)
Genus	Arion	Lagenorhynchus
Species	Arion rufus	Lagenorhynchus albirostris

Evolutionary Relationship

Chocolate arion and Dauphin A Bec Blanc share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Chocolate arion

VU — Vulnerable

Dauphin A Bec Blanc

NE — Not Evaluated

Physical Characteristics

Attribute	Chocolate arion	Dauphin A Bec Blanc
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Chocolate arion

Habitat

Inhabits temperate broadleaf and mixed forests and Mediterranean forests and woodlands within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found across 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.

Dauphin A Bec Blanc

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Chocolate arion

The Chocolate Arion (Arion rufus), also known as the Large Red Slug or Chocolate Slug, is one of Europe's largest terrestrial slugs, with adults reaching up to 15 centimetres in length. It belongs to the family Arionidae within the phylum Mollusca, and despite its common name, adults display highly variable colouration ranging from reddish-orange to dark brown and nearly black — only certain colour morphs exhibit the chocolate-brown hue that partly inspired the name. Arion rufus is native to western and central Europe, where it inhabits woodland, hedgerows, gardens, agricultural land, and other moist habitats. It is also established as an introduced species in parts of North America. Like other arionid slugs, it is primarily a detritivore and herbivore, consuming dead plant material, fungi, living plant tissue, and sometimes carrion. It shelters under logs, stones, and leaf litter during dry or cold conditions, becoming active — particularly at night — during warm, moist weather. Chocolate arion can cause significant damage to gardens and crops. Reproduction is hermaphroditic; slugs exchange sperm and lay batches of translucent eggs in soil or under debris. The IUCN classifies this species as Vulnerable, reflecting pressures on native European populations from habitat change and, possibly, competition and hybridisation with related Arion species.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden