WAmphiaspididae
WArandaspida
WArchipelepis
WAriaspidae
WAteleaspididae
WBirkeniidae
WBoreaspis
WCardipeltis
WCephalaspidae
WCoelolepidae
WCtenaspidae
WCyathaspididae
WFurcacaudidae
WGabreyaspididae
WHibernaspis
WLasanius
WMyllokunmingiidae
WOlbiaspididae
WPharyngolepis
WPhlebolepididae
WProtaspididae
WProtopteraspididae
WPsammosteidae
WPteraspididae
WPterygolepis
WRhyncholepis
WArandaspida
WTolypelepidida
WTraquairaspidiformes
WWeigeltaspis
WZenaspididae