Parent taxon: Placodermi according to G. C. Young 2010
See also Denison 1975, Denison 1978, Dineley and Metcalf 1999, Long 2011 and Sepkoski 2002
Sister taxa: Acanthothoraciformes, Antiarcha, Antiarchiformes, Arthrodira, Asiacanthus, Austroptyctodus, Brindabellaspida, Campbellodus, Changyonophyton, Coccostei, Coelosteichthys, Deinodus, Hybosteus, Neopetalichthys, Nessariostoma, Oestophorus, Petalichthida, Petalichthyida, Petalichthyida, Phyllolepida, Pseudopetalichthyida, Pseudopetalichthyiformes, Ptychostei, Ptyctodontida, Rhenanida, Rhenaniformes, Sedowichthys, Stensioellida, Tollichthys, Yunnanacanthus
Subtaxa: Breizosteus Kolymaspidae Murrindalaspis Palaeacanthaspidae Radotinidae Weejasperaspis
Ecology: nektonic carnivore
Distribution:
• Devonian of Australia (1 collection), the Czech Republic (1), Japan (1), the Russian Federation (1)
Total: 4 collections each including a single occurrence