Description: A large keeled slug with a characteristic warm buff to grayish-buff ground colour conspicuously spotted with brown or black. Respiratory pore with a pale rim and mantle with two thin dark lateral bands. Keel yellowish to white. Sole pale, mucus colourless. Very rare. 70-100 mm.

World Distribution: This species may have originated in south-east Europe and spread by human agency north-west to the British Isles, like several other slug species. However, it is difficult to rule it out as a native. Distribution type: European Southern-temperate (83).

Irish Distribution: Stelfox (1911a) refers to spotted keeled slugs having been found near Blarney and Aghada in East Cork. Dissection was not performed on these and the records remained unconfirmed until Cawley (1996b) discovered the present species on roadsides near Blarney. More recently Pascal Sweeney (pers. comm.) has reported a live specimen from woods at Rostellan 3 km from Stelfox's Aghada site.

Ecology:

• Usually found concealed in the lower layers of deep beech or oak leaf litter
• Also occurs under dead wood and deeply embedded stones - but always in shaded woodland environments on shallow soils over limestone
• The scarcity of higher plants in these places suggests a diet of leaf litter, spiced seasonally with fungi or dead animal remains
• Eggs have been produced in captivity in the autumn but the timing of reproduction in the wild is uncertain

Key Identification Features:

• A large keeled slug with a characteristic warm body colour
• Body a warm buff to greyish-buff speckled with brown to black spots and with two thin lateral bands on the mantle
• Breathing pore with a pale rim
• Keel yellowish to white
• Mucus colourless, moderately sticky
• Mantle granular with deep but inconspicuous horseshoe-shaped groove

Red list status:

• Vulnerable (VU).

Distribution Map from NBN: Tandonia rustica at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Tandonia rustica at iNaturalist World Species Observations database.

GBIF data for Tandonia rustica | Classification: Gastropoda, Stylommatophora, Milacidae, Tandonia

Thumbnails for genus Tandonia