Deroceras reticulatum, common names "grey field slug" and "grey garden slug", is a species of small air-breathing land slug, a terrestrial pulmonate gastropod mollusc which is important as an agricultural pest.
This slug can be up to 35 mm in length when extended. It has a short keel at the back of the body.
The body is very variable in color. It is often mottled with lighter or darker shades of grey, and the ground color can be whitish, cream, through brownish-yellow to blue-black. The body is often reticulated with darker grooves.
The mucus in this species is milky-white and sticky.