[Phylum] Chordata Bateson, 1885 - chordates Subphylum Craniata auct. Infraphylum Vertebrata Lamarck, 1801 - vertebrates Superclass †Pteraspidomorphi Goodrich, 1909 [monotypic] Class †Pteraspidomorpha Subclass †Heterostraci Lankester, 1868 Order †Pteraspidiformes Berg, 1940 Suborder †Psammosteoidei Kiaer, 1932 Family †Psammolepididae Tarlo, 1962 1 Genus †Psammolepis Agassiz, 1844