Hinge line

A hinge line is an imaginary longitudinal line along the dorsal edge of the shell of a bivalve mollusk where the two valves hinge or articulate.

The hinge line can easily be perceived in these images of a mussel shell and an ark shell.

[1][2][3] The hinge teeth, structures which control the articulation of the valves, are often but not always situated along the hinge line.

This bivalve-related article is a stub.

You can help Wikipedia by expanding it.