Psammosteidae

Model of Drepanaspis gemuendensis at the Smithsonian National Museum of Natural History.

• North America
• Europe
• Siberia

The Psammosteidae are an extinct taxon of meeresbewohnenden vertebrates. They were among the Heterostraci, a subgroup of the Pteraspidomorphi, bringing the Psammosteidae to the jawless ( Agnatha ) included, ie to distant relatives of today's fish.

Verification required fossils of Psammosteidae in the Silurian and Devonian (before 430-370 million years ago). They had a skull tank, but do not have a jaw. Compared to the other Heterostraci having a length of about 5 - 30 cm achieved the Psammosteidae up to 150 cm were significantly larger.