Pteraspidomorpha - Traquairaspidida
Parent taxon: Heterostraci according to E. J. Loeffler and D. L. Dineley 1976
Sister taxa: Amphiaspidiformes, Aporemaspis, Ariaspididae, Aserotaspis, Cardipeltida, Cardipeltidae, Cardipeltiformes, Ceraspidae, Corvaspidida, Corvaspidiformes, Cyathaspida, Cyathaspidiformes, Drepanaspidae, Guerichosteidae, Lepidaspidida, Lepidaspidiformes, Munchoaspis, Olbiaspidida, Palaeaspidi, Psammolepis, Psammosteiformes, Pteraspidi, Pteraspidiformes, Rimasventeraspis, Strosipherus, Tesseraspidida, Tesseraspidiformes, Tolypelepidida, Tolypelepidiformes, Toombsaspis, Traquairaspidiformes, Dyreaspis, Seretaspis, Asketaspis, Obliaspis, Pionaspis, Strophisterus, Corveolepis, Pilolepsis, Poriferaspis, Allocryptaspis, Pycnaspis, Gunaspis, Grumantaspis, Clydonaspis, Steinaspis, Kiangsuaspis, Karelosteus, Irregulariaspis, Anatolepsis, Schizosteus, Archodus, Listraspis, Alainaspis, Ennosviaspis, Yoglinia, Homaspidella, Athenaegis
Subtaxa: none
Ecology:
Distribution: found only at Pressure Point, Somerset Island [Peel Sound Fm] (Silurian of Nunavut)