All illustrations by Felicity Rose Cole
1 Great grey slug Limax maximus (above)
Up to 20cm. Also called the leopard slug due to its dark blotches. Gardens and woods; can climb trees and walls.
2 Yellow slug Limax flavus
Up to 13cm. Yellower than the similar great grey slug. Gardens, cellars and outhouses; can climb walls.
3 Large black slug Arion ater
Up to 13cm. Typically black with an orange frill (above); brown and orange forms also occur. Gardens and woodland.
4 Tree slug Lehmannia marginata
Up to 8cm. Like a small great grey slug. Woods and rocky places; climbs trees and rocks to graze algae and lichen.
5 Worm slug Boettgerilla pallens
Up to 5.5cm. Greyish and worm-like. Gardens, under bricks or rubbish. Introduced; first noted in UK in 1972.
6 Prickly snail Acanthinula aculeata
Shell 2mm (a hand lens is needed to examine this species). Unmistakable prickles. Woods and hedgerows.
7 Crystal snail Vitrea crystallin
Shell 3–4mm. Near-circular, glassy, transparent shell with regular whorls. Woods, meadows and road verges.
8 Rounded snail Discus rotundatus
Shell 5–7mm. Circular shell with radiating grooves and brown bands. Woods, gardens and hedgerows.
9 Girdled snail Hygromia cinctella
Shell 10–12mm. Pale brown shell has a white ridge or keel. Plant nurseries and gardens. Introduced; spreading fast.
10 Common chrysalis snail Lauria cylindracea
Shell 3–4mm. Commonest of several similar snails. Gardens, woods and rocky places; often under ivy on walls.
11 Common door-snail Clausilia bidentata
Shell up to 12mm. Woods and rocky places. One of several spire-shaped snails found on tree bark or walls.
12 Plaited door-snail Cochlodina laminata
Shell 15–17mm. Larger and more robust than Clausilia, with ‘polished wood’ tones. Woods and rocky places.