Pteraspidomorpha - Tesseraspidiformes
Parent taxon: Heterostraci according to R. Van Der Laan 2019
Sister taxa: Amphiaspidiformes, Aporemaspis, Ariaspididae, Cardipeltida, Cardipeltidae, Cardipeltiformes, Ceraspidae, Corvaspidida, Corvaspidiformes, Cyathaspida, Cyathaspidiformes, Drepanaspidae, Guerichosteidae, Lepidaspidida, Lepidaspidiformes, Munchoaspis, Olbiaspidida, Palaeaspidi, Protaspidae, Psammolepis, Psammosteiformes, Pteraspidi, Pteraspidiformes, Rimasventeraspis, Strosipherus, Tesseraspidida, Thelodontidae, Tolypelepidida, Tolypelepidiformes, Toombsaspis, Traquairaspidida, Traquairaspidiformes
Subtaxa: Natlaspididae Tesseraspididae
Ecology:
Distribution:
• Devonian of Canada (1: Northwest Territories collection), Lithuania (1), the Russian Federation (1), Ukraine (1), the United Kingdom (2)
• Silurian of Lithuania (1), the United Kingdom (1)
Total: 8 collections including 9 occurrences