Pteraspidomorpha - Tolypelepidiformes
Parent taxon: Heterostraci according to R. van der Laan 2019
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, Toombsaspis, Traquairaspidida, Traquairaspidiformes, Kiangsuaspis, Clydonaspis, Irregulariaspis, Obliaspis, Athenaegis, Anatolepsis, Asketaspis, Dyreaspis, Grumantaspis, Karelosteus, Homaspidella, Pionaspis, Archodus, Ennosviaspis, Corveolepis, Gunaspis, Allocryptaspis, Alainaspis, Steinaspis, Listraspis, Seretaspis, Pilolepsis, Poriferaspis, Pycnaspis, Yoglinia, Strophisterus, Schizosteus
Subtaxa: Tolypelepididae
Ecology:
Distribution:
• Silurian of Canada (2: Northwest Territories, Nunavut collections), Estonia (3), Poland (1), the Russian Federation (2)
Total: 8 collections each including a single occurrence