Alternative spelling: Placodermata
Parent taxon: Gnathostomata according to R. van der Laan 2019
See also Bryant 1932, Denison 1975, Dineley and Metcalf 1999, Hay 1902, Jaekel 1911, Kiessling 2004, Long 2011, Nelson et al. 2016, Säve-Söderbergh 1934 and Sepkoski 2002
Sister taxa: Acanthodii, Chondrichthiomorphi, Chondrichthyes, Eugnathostomata, Ichthyes, Janusiscus, Minjinia, Osteichthyes, Placodermiomorphi, Plectrodus, Qilinyu, Ramirosuarezia, Xiushanosteus
Subtaxa: Acanthothoraci Acanthothoraciformes Antiarchi Arthrodira Asiacanthus Austroptyctodus Bianchengichthys Brindabellaspida Campbellodus Changyonophyton Coccostei Coelosteichthys Cratoselachiidae Deinodus Entelognathus Hybosteus Neopetalichthys Nessariostoma Oestophorus Petalichthida Petalichthyida Petalichthyida Pseudopetalichthyida Pseudopetalichthyiformes Ptychostei Ptyctodontida Rhenanida Rhenaniformes Sedowichthys Stensioelliformes Tollichthys Wangolepis Yunnanacanthus
Ecology: nektonic carnivore