Subclass †Heterostraci Lankester, 1868
Count: [†*] †1f;23g;30s
   1 Genus †Athenaegis Soehn & Wilson, 1990
  Count: [†*] †1s
   2 Family †Cyathaspididae Kiaer, 1932, nom. praeval.
  Count: [†*] †22g;29s