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, Psammosteiformes, Pteraspidi, Pteraspidiformes, Rimasventeraspis, Strosipherus, Tesseraspidida, Tesseraspidiformes, Tolypelepidida, Tolypelepidiformes, Toombsaspis, Traquairaspidida, Traquairaspidiformes, Pilolepsis, Allocryptaspis, Poriferaspis, Karelosteus, Clydonaspis, Yoglinia, Gunaspis, Corveolepis, Obliaspis, Dyreaspis, Seretaspis, Anatolepsis, Strophisterus, Listraspis, Steinaspis, Schizosteus, Homaspidella, Archodus, Ennosviaspis, Pycnaspis, Irregulariaspis, Grumantaspis, Kiangsuaspis
Subtaxa: Cyathaspidei Poraspidei
Ecology: planktonic suspension feeder