Lehmanosteus

Lehmanosteus is an extinct monospecific genus of arthrodire placoderm fish, named after French paleontologist Jean-Pierre Lehman. The type species Lehmanosteus hyperboreus was described in 1984, and was found in Early Devonian strata of the Wood Bay Formation on the island of Spitsbergen, Svalbard in Norway.

It is one of the more basal members of the order Arthrodira, as shown in the cladogram below: