Fragile shell up to 3mm in length. It is coloured dirty white with a red tint both inside and outside. The surface of the shell is sculptured with concentric and raditaing lines.

Brittle shell up to 30cm in length. It is light to dark brown in colour both inside and outside but inside is glossy. The surface is sculptured with concentric lines and 8 to 12 radiating ribs. There are no teeth on the hinge.

6-8mm

Boettgerilla pallens Simroth 1912

Small to medium slug, extended length 3 – 4 cm. Pale translucent greyish-yellow, with keel from tip of tail right up to edge of the mantle; back and head darker bluish-grey. Very narrow, almost worm-like, when fully extended. Sole pale yellow, mucus colourless.

Tandonia sowerbyi (Férussac1823)

Medium to large slug – extended length 6 – 7.5 cm. Body pale brownish-grey speckled with black, with grooves between tubercles also pigmented. Pneumostome with pale orange rim. Keel lighter than body, usually yellow or orange, crinkled when animal is contracted, not truncate. Sole whitish, mucus thick, yellowish and sticky. Some colour variants occur, and the keel is occasionally the same colour as the body.

Tandonia budapestensis (Hazay, 1881)