Common garden slug  (Arion distinctus)

Common and widespread in Britain (1).

Once included in the aggregate species Arion hortensis agg, the garden slug (Arion distinctus) is still confused with the similar species Arion hortensis and Arion owenii (2). The common garden slug is a yellow-grey colour with a bluish-black head and tentacles (2). Towards the rear end of the slug there is a yellowish stripe in the middle of the back, there are also stripes around the sides of the body (2).

Widespread throughout Britain (1) and also found in Europe and North America (2).

This slug is typically found in habitats with a strong human influence such as gardens and parks (2).

The common garden slug breeds throughout much of the year and can be a serious pest of gardens as they attack cultivated plants, fruit, tubers and bulbs (1), which are eaten by means of a rasping tongue known as a radula. They emerge at night, and spend the day in moist places beneath stones, logs and other objects (1).

Slugs are related to snails; in the genus Arion, the shell is reduced to a group of calcareous granules below the 'mantle', which appears as a bulge on the upper surface of the slug (3).

Slugs are hermaphrodites, meaning that individuals possess both male and female reproductive organs, but self-fertilisation does not occur. During courtship, members of a pair follow each other in circles, whilst feeding on their partner's mucus trail (3).

This slug is not threatened.

Conservation action has not been targeted at this common species.

For more on invertebrates and their conservation see Buglife, the Invertebrate Conservation Trust at:
http://www.buglife.org.uk/

• Calcareous: containing free calcium carbonate, chalky.
• Hermaphrodite: possessing both male and female sex organs.
• Radula: in some molluscs, a narrow structure that bears teeth and is used to rasp at food.

1. National Biodiversity Network Species Dictionary (Jan 2003): http://www.nhm.ac.uk/nbn/
2. Pfleger, V. & Chatfield, J. (1983) A guide to snails of Britain and Europe. The Hamlyn Publishing Group, Ltd., London.
3. Janus, H. (1982) The illustrated guide to molluscs. Harold Starke Ltd., London.