Description: A large roundback slug similar to Arion ater but with slightly brighter colouration, a much brighter foot fringe and sole and a less strong rocking response. Juveniles possess distinct lateral bands. Found in drier, warmer places, including gardens. 70-140 mm.

World Distribution: True range is uncertain due to confusion with related species. Probably only occurs in the extreme coastal fringes of Europe. Distribution type: Oceanic Temperate (71).

Irish Distribution: Widespread in gardens in the east. In the west more in natural habitats near the sea.

Ecology:

• Probably common in gardens in the main urban centres of the east, but much under-recorded
• Elsewhere, on dry coastal habitats such as dunes and heathy hill slopes
• Recorded from several western islands
• Not known to eat or damage green vegetable material but its presence in gardens will alert suspicions to that effect

Key Identification Features:

• A large roundback slug varying in colour from whitish through orange and browns to black, with the sides of the body below the mantle pale in darker specimens
• Foot fringe always a rich orange to carmine-red, often contrasting with a darker upper body
• Sole paler than the upper body and usually with an orange flush near the head end; in dark specimens strong lineolations radiating inwards from the sides, are present
• Juveniles are pale grey-brown with dark brown to black bands edged above with pale reddish or yellow
• Rocking response is muted, and sometimes not exhibited at all

Taxonomy:

• British and Irish A. rufus have been well characterized by Quick (1960) and are probably distinct from the 'red slug' of Continental authors (e.g. Chevallier, 1981).

Red list status:

• Least concern (lc).

Distribution Map from NBN: Arion ater rufus at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Arion ater rufus at iNaturalist World Species Observations database.

GBIF data for Arion rufus | Classification: Gastropoda, Stylommatophora, Arionidae, Arion

Thumbnails for genus Arion