Pteraspidomorpha - Cyathaspidiformes
Parent taxon: Heterostraci according to R. van der Laan 2019
See also Elliott 2016, Elliott 2013, Long 2011 and Nelson et al. 2016
Sister taxa: Amphiaspidiformes, Aporemaspis, Ariaspididae, Aserotaspis, Cardipeltida, Cardipeltidae, Cardipeltiformes, Ceraspidae, Corvaspidida, Corvaspidiformes, Cyathaspida, Drepanaspidae, Guerichosteidae, Lepidaspidida, Lepidaspidiformes, Munchoaspis, Olbiaspidida, Palaeaspidi, Psammolepis, Psammosteiformes, Pteraspidi, Pteraspidiformes, Rimasventeraspis, Strosipherus, Tesseraspidida, Tesseraspidiformes, Tolypelepidida, Tolypelepidiformes, Toombsaspis, Traquairaspidida, Traquairaspidiformes, Strophisterus, Listraspis, Allocryptaspis, Dyreaspis, Gunaspis, Archodus, Yoglinia, Obliaspis, Kiangsuaspis, Schizosteus, Pilolepsis, Clydonaspis, Seretaspis, Steinaspis, Pycnaspis, Grumantaspis, Karelosteus, Anatolepsis, Poriferaspis, Corveolepis, Irregulariaspis, Homaspidella, Ennosviaspis
Subtaxa: Amphiaspidoidei Cyathaspididae Cyathaspidoidei Hibernaspidoidei Siberiaspidoidei