12 Littorina compressa. 8mm high. North coast of Anglesey, Wales. March 2015.

12 Littorina compressa. 8mm high. North coast of Anglesey, Wales. March 2015.

Dorsum of head and body intensely pigmented black (sometimes less so). Snout unpigmented yellowish at tip.
Cephalic tentacles taper rapidly from greatly swollen base bearing eye; translucent yellowish-white with pair of blackish dorsolateral lines.
Course of anterior aorta visible as long unpigmented band running diagonally across body to base of right tentacle.
Upper surface of foot white (sometimes yellowish white; often with black or grey lines and speckles).