All living cocculiniforms have cap-shaped shells. The apex of the shell is typically situated at the center or nearer the posterior end of the shell. Shells are sculpted with concentric growth lines, and in some species, additional fine radial threads or beads extend from the apex to the shell margin, while in other species, the surface appears cancel-late. The shell aperture is typically oval. The inner surface of the shell bears a horseshoe-shaped muscle scar that opens anteriorly where the head is located. The head is not very flexible and the mouth opens ventrally for grazing on the substrate. Copulatory organs are present and are typically part of the right cephalic tentacle. The Cocculiniform radula is rhipdoglossate, as in the Vetigastropoda and Neritopsina. The Cocculiniform gill consists of a vestigial pseudoplicate structure that does not resemble the typical molluscan gill or ctendium.
Cocculiniformia range in size from about 0.2-0.6 in (5-15 mm) in length, and are white in color and covered with a periostracum.
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