Müller O.F., 1776
Description (shell):
Shell large, bubble-like, fragile, glossy, up to six whorls forming a rather flat spire.
Size:
Up to 40 mm.
Colour:
White to pale brown.
Animal:
Body up to 60 mm, pale grey to orange, often streaked anteriorly with blotchy lines of purplish-brown, covered with white and dark spots. Head indented anteriorly, expanded laterally to form flattened tentacular lobes. Parapodial lobes enlarged, used for evasive swimming action; covering lateral and dorsal areas of shell when at rest (A. bullata-animal).
Habitat:
In and on soft fine mud, in sheltered bays formerly favoured by Zostera. Herbivorous. Lower shore to 370 m.
Distribution:
Not uncommon (Distr. A. bullata).