Subphylum [Vertebrata] Cuvier, 1812 - vertebrates Class Agnatha Cope, 1889 Subclass †Thelodonti Kiaer, 1932 Order †Shieliiformes Märss, Wilson & Thorsteinsson, 2002 [monotypic] Family †Shieliidae Märss, Wilson & Thorsteinsson, 2002 Genus †Praetrilogania Blom, 1999