Barythaerus is a small genus of marine bivalve molluscs of the family Thraciidae.[2][3] The genus is endemic to the waters off southern New Zealand.[3] Shells have been found at depths of 27–805 m (89–2,641 ft). Live specimens have been found from bryozoan and shell substrates at intermediate depths (55–183 m).[1]
| Barythaerus | |
|---|---|
 | |
| Type specimen of Barythaerus biconvexus from the collections of Te Papa | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Family: | Thraciidae |
| Genus: | Barythaerus B. A. Marshall, 2002[1] |
| Species | |
2 species (see text) | |
Species
There are two recognized species:[2]
- Barythaerus biconvexus (A. W. B. Powell, 1927)
- Barythaerus cuneatus (A. W. B. Powell, 1937)
Description
Barythaerus are small bivalves, with the larger species (Barythaerus cuneatus) reaching 5.5 mm (0.22 in) in length. The shell is stout with a beak located in the posterior ⅓–¼ of the shell. Only the right valve has a prominent tooth. They resemble Parvithracia but are more stout and oblique.[1]