Chocolate arion
Arion rufus
Arion ater rufus, also known as the red slug, large red slug, chocolate arion and European red slug, is a subspecies of land slug in the family Arionidae, the roundback slugs.
34
Countries
Photo: Wikimedia Commons (CC) via https://en.wikipedia.org/wiki/Arion_ater_rufus
Taxonomy & Classification
Kingdom
Animalia
Phylum
Mollusca
Class
Gastropoda
Order
Stylommatophora
Family
Arionidae
Genus
Arion
Chocolate arion belongs to the family Arionidae, order Stylommatophora, within the Gastropoda class.
Species Profile
Arion ater rufus, also known as the red slug, large red slug, chocolate arion and European red slug, is a subspecies of land slug in the family Arionidae, the roundback slugs.
The Chocolate arion faces significant threats from habitat degradation and fragmentation due to agricultural intensification, urbanization, and changes in land management practices. Climate change poses additional risks through altered precipitation patterns and temperature regimes that affect the moist conditions essential for this species' survival. Pollution from pesticides and fertilizers further compounds these pressures on vulnerable populations.
Key Facts
Habitat & Distribution
Inhabits moist deciduous and mixed woodlands, gardens, parks, and agricultural areas with adequate ground cover and organic matter. Requires consistently humid microhabitats including leaf litter, compost heaps, and areas with dense vegetation that provide shelter and moisture retention.
Threats
Habitat loss and fragmentation from agricultural intensification
Urban development and infrastructure expansion
Changes in traditional land management practices
Climate change affecting moisture and temperature regimes
Pesticide and fertilizer pollution
Found in 34 Countries
National vs Global Threat Status
How this species is assessed at the national level compared to its IUCN global status (VU).
| Country | National Status | Global Status | Comparison |
|---|---|---|---|
| EU | LCLeast Concern | VUVulnerable | Lower local risk |
| EU | LCLeast Concern | VUVulnerable | Lower local risk |
National Red List data sourced from the National Red List Project (nationalredlist.org, ZSL) and country-specific Red List authorities.
Community Sightings
Report a sightingNo community sightings yet. Be the first to report!
Sources & Attribution
How to Cite
IUCN: IUCN (2025). The IUCN Red List of Threatened Species. Version 2025-1. Available at: https://www.iucnredlist.org. doi:10.2305/IUCN.UK.2025-1.RLTS
GBIF: GBIF.org (2025). GBIF Home Page. Available at: https://www.gbif.org
National Red Lists: ZSL (2025). National Red List. Zoological Society of London. Available at: https://www.nationalredlist.org
This page: SpeciesRadar (2025). Chocolate arion (Arion rufus). SpeciesRadar: Intelligence for Earth's Biodiversity. Available at: https://speciesradar.org/species/chocolate-arion