Mollusca : Gastropoda : Stylommatophora : LimacidaeSnails and slugs

Limax cinereoniger Wolf, 1803

Ash-black slug

Limax cinereoniger

Description: A very large slug, body with grey to mid brown ground colour and two faint lateral bands on each side. Similar in habits and appearance to dark forms of L. maximus but generally darker and adults are rarely spotted or banded and usually have a contrasting, paler keel. The sole differs in being tripartite with pale central and contrasting dark outer zones. Widespread but local in old woods. 150-200 mm.

World Distribution: There is a complex of related species in Europe so the true range is difficult to determine. Possibly Europe-wide except the extreme north and extreme south. Distribution type: European Wide-temperate (63).

Irish Distribution: Local and comparatively rare in Ireland, but apparently widespread. Less rare in northern counties possibly due to differences in forestry practices between N. Ireland and Republic of Ireland.

Ecology:

  • Mostly recorded from old, minimally disturbed broadleaf woodlands
  • Also on cliffs with relic woodland vegetation on western coasts
  • Underplanting broadleaf woods with conifers (practised in RoI) is probably harmful

Key Identification Features:

  • A very large, dark slug with tripartite sole - black or dark grey on either side and white down the middle
  • Keel about ⅔ the distance from mantle to tail, pale, whitish or yellowish
  • Tentacles obscurely spotted brownish or grayish
  • Juveniles have uniformly pale soles and are usually a warm buff colour with broken, dark, lateral bands
  • Breathing pore at rear of the mantle
  • Mantle with shallow concentric grooves centred on the back

Red list status:

  • Vulnerable (VU).

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

iNaturalist: Limax cinereoniger at iNaturalist World Species Observations database.

GBIF data for Limax cinereoniger | Classification: Gastropoda, Stylommatophora, Limacidae, Limax

Thumbnails for genus Limax

 Anderson, R., 2024. Limax cinereoniger. Wolf, 1803. [In] MolluscIreland.
https://www2.habitas.org.uk/molluscireland/species.php?item=107. Accessed on 2024-12-26.