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, Pionaspis, Yoglinia, Clydonaspis, Dyreaspis, Homaspidella, Grumantaspis, Strophisterus, Schizosteus, Asketaspis, Alainaspis, Archodus, Anatolepsis, Poriferaspis, Obliaspis, Seretaspis, Pilolepsis, Corveolepis, Irregulariaspis, Listraspis, Kiangsuaspis, Athenaegis, Ennosviaspis, Steinaspis, Karelosteus, Allocryptaspis, Pycnaspis, Gunaspis
Subtaxa: Amphiaspidoidei Cyathaspididae Cyathaspidoidei Hibernaspidoidei Siberiaspidoidei
Ecology: