Full reference: O. Jaekel. 1911. Die Wirbeltiere. Eine Übersicht über die Fossilen und Lebenden Formen [The Vertebrates. An Overview of the Fossil and Living Forms] viii-252
Parent taxon: Placodermata according to O. Jaekel 1911
Sister taxa: Acanthothoraci, Acanthothoraciformes, Antiarcha, Antiarchiformes, Arthrodira, Asiacanthus, Austroptyctodus, Brindabellaspida, Campbellodus, Changyonophyton, Coccostei, Coelosteichthys, Deinodus, Hybosteus, Neopetalichthys, Nessariostoma, Oestophorus, Petalichthida, Petalichthyida, Petalichthyida, Phyllolepida, Pseudopetalichthyida, Pseudopetalichthyiformes, Ptyctodontida, Rhenanida, Rhenaniformes, Sedowichthys, Stensioellida, Tollichthys, Yunnanacanthus
Subtaxa: Phlyctaenaspi
Ecology: nektonic carnivore
Distribution: there are no occurrences of Ptychostei in the database