vertebrates Lamarck, 1801 - vertebrates see Infraphylum Vertebrata Lamarck, 1801 Class †Pteraspidomorphi Goodrich, 1909 see Class Pteraspidomorpha Subclass †Heterostraci Lankester, 1868 Order †Tesseraspidiformes Halstead, 1962 Family †Tesseraspididae Berg, 1955, nom. praeval. Genus †Tesseraspis Wills, 1935 †Tesseraspis mutabilis (Brotzen, 1934)