Pteraspidomorpha - Cyathaspida
Full reference: J. Kiaer. 1932. The Downtonian and Devonian vertebrates of Spitsbergen. IV, Suborder Cyathaspida. Skrifter Om Svalbard Og Ishavet 52:1-26
Parent taxon: Heterostraci according to J. Kiaer 1932
See also Loeffler and Dineley 1976
Sister taxa: Amphiaspidiformes, Aporemaspis, Ariaspididae, Aserotaspis, Cardipeltida, Cardipeltidae, Cardipeltiformes, Ceraspidae, Corvaspidida, Corvaspidiformes, Cyathaspidiformes, Drepanaspidae, Guerichosteidae, Lepidaspidida, Lepidaspidiformes, Munchoaspis, Olbiaspidida, Palaeaspidi, Psammolepis, Psammosteiformes, Pteraspidi, Pteraspidiformes, Rimasventeraspis, Strosipherus, Tesseraspidida, Tesseraspidiformes, Tolypelepidida, Tolypelepidiformes, Toombsaspis, Traquairaspidida, Traquairaspidiformes, Yoglinia, Allocryptaspis, Schizosteus, Obliaspis, Gunaspis, Asketaspis, Grumantaspis, Ennosviaspis, Homaspidella, Karelosteus, Steinaspis, Listraspis, Corveolepis, Seretaspis, Strophisterus, Alainaspis, Kiangsuaspis, Irregulariaspis, Poriferaspis, Pilolepsis, Dyreaspis, Anatolepsis, Archodus, Pycnaspis, Clydonaspis, Athenaegis, Pionaspis
Subtaxa: Cyathaspidei Homalaspidella Poraspidei
Ecology: