Boreaspis (Boreas shield).
Classification: Chordata, Osteostraci, Benneviaspidida.
Size: Around 13 centimetres long.
Known locations: Spitsbergen.
Time period: Early Devonian.
Fossil representation: Many individuals.
Boreaspis is a jawless fish genus noted for having a triangular head shield formed from an elongated snout and two pointed extensions that protruded from the base to the sides. These would have increased hydrodynamic efficiency while the snout could also be used to stir up sediment.