Lehmannia valentiana

Biological Name

Ambigolimax valentianus (A. Férussac, 1822)
previously known as Lehmannia valentiana

Common Name

Greenhouse slug

Other Common Names

Valencia slug, Iberian threeband slug


The greenhouse slug has a short keel at the back of the body. It is a medium-sized slug, 50 to 70 mm long, has a yellow-grey body with a dark colour band on each side and two dark longitudinal bands. The pneumostome is located in the posterior half of the mantle, the mucus is colourless.

Other Similar Species

Ambigolimax nyctelius, Lehmannia marginata

Biological Notes

This ground-dwelling species has an annual life-cycle. The greenhouse slug is an omnivorous species, with a nocturnal feeding activity.

Geographic Distribution

Originally from the Iberian Peninsula, the greenhouse slug has spread into many regions outside Europe. It lives in North and South America, South Africa, Australia, Asia. In northern areas it is found mostly in greenhouses.


The greenhouse slug lives in disturbed habitats including urban habitats and in greenhouses.

Crops at Risk

It is a pest of all kind of ornamental plants and vegetables grown in greenhouses and gardens.

Damage Caused/Symptoms

The greenhouse slug often causes foliar damage to flowers and vegetables like lettuce. Furthermore, feeding damage often leads to decay and the presence of slugs and contamination by faeces devalues the product.

Impact and Severity

Most severe damage occurs to seedlings and the harvested product by contamination with slime and faeces.

Prevention and Control

Once established in the greenhouse, the greenhouse slug is difficult to control, as there are many places to shelter.

Natural Predators

The slug-parasitic nematode Phasmarhabditis hermaphrodita is used as a biological control agent against the greenhouse slug.