Hammer Oyster (BIRUG 19117)

3D Model

BIRUG 19117 is a recent specimen of Malleus sp. – a member of the bizarre group of bivalves known as ‘hammer oysters’, though are not directly related to true oysters. The group is so-named because the shells usually form the shape of a ‘T’ or a hammer; although in this individual the ‘handle’ or vertical part of the ‘T’ is highly curved. The cross-piece of the ‘T’ is where the hinge is located, and is often buried in sand, or is secured by a bundle of thread-like structures called a “byssus” to rocks within a coral reef.

The animal’s bizarre shape ensures that its hinge is secured in sand or other materials, whilst its long valves poke up above the sediment, allowing the animal to filter-feed.

The name “Malleus” comes from the Latin for “hammer” or “mallet”, a name also given to the tiny malleus bone within the human ear.

This specimen was collected in the Maluku Islands in Indonesia in 1884 by G. B. Sowerby III. Scanning was performed by Sian Miller using an Artec Spider 3D scanner.