MolluscIreland - land and freshwater
  • Arion (Kobeltia) intermedius Normand 1852 Hedgehog slug
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Arion (Kobeltia) intermedius
© Dr Roy Anderson
Arion (Kobeltia) intermedius
© Dr Roy Anderson
Arion (Kobeltia) intermedius
© Dr Roy Anderson

Map hosted by the National Biodiversity Data Centre, Waterford
To view the species profile on Biodiversity Maps and access the live map, please click on the map.


One of the garden slug group, but much smaller than the others and with points or prickles on the dorsal tubercles which earns it the popular name of hedgehog slug. Colour variable - may be banded or unbanded.

Key characteristics

  • A small slug, easily the smallest and most compact (nearly bell-shaped at rest) of the garden slug group
  • Very variable in colour, from unbanded pure white or orange to pale grey with thin lateral bands, or charcoal grey with black lateral bands (the latter is rare)
  • Tubercles coming to points giving a 'prickly' appearance at rest (observe closely from the side when the tubercles appear to glisten around the minute points at their apexes)
  • Sole yellow to orange
  • Tentacles grey - compare the purplish tones in the tentacles of immature Arion owenii which can otherwise closely resemble mature A. intemedius in appearance


15-20 mm.

World Distribution

Found near coasts from southern Scandinavia to Portugal and the Azores. Distribution type: Oceanic Wide Temperate (61).

GBIF distribution map [open in new tab]

Irish Distribution

Common everywhere but particularly in the west.


  • In grassland of all kinds and in a variety of woodland types
  • Appears to avoid dry or excessively disturbed environments such as sand dunes and gardens (Boycott, 1934)
  • Often found on peaty soils but not at high altitude

Red List status

  • Least concern (lc).

Wikipedia link

Wikipedia page for Arion intermedius

 Anderson, R., (2016). Arion (Kobeltia) intermedius Normand 1852. [In] MolluscIreland. Accessed on 2024-06-21.