Description

Glycymeridae shells are similar to
Ark shells in having a taxodont hinge; namely a hinge showing along the edges, two rows of similarly shaped teeth arranged in a chevron-like paattern (top to bottom, at right in the picture below). Generally, the shell is so symmetrical that identifying the front from posterior ends is difficult without seeing the live mollusc. The foot would protrude from the front end, and the siphons from the posterior. In the specimen shown here, a faint muscle scar (near the bottom right) identifies its posterior end (Keene, 1958).

 

While not deepwater forms, the Glycymeridae do not tolerate intertidal conditions well. They are generally dredged from moderately deep waters. 

Classification

Class: Bivalvia

Subclass: Pteriomorphia

Order: Arcoida

Superfamily: Limopsacea

Family: Glycymerididae

 

Single Genus: Glycymeris

Glycymeris gigantea Reeve, 1843
Giant Bittersweet