Chondrichthyes - Ischnacanthida
Parent taxon: Acanthodii according to P. Janvier and M. S. Riglos 1986
See also Denison 1979 and Sepkoski 2002
Sister taxa: Acanthodi, Acanthodida, Acanthodiformes, Antarctonchus, Archaeacanthus, Byssacanthoides, Campylodus, Climatiida, Climatiiformes, Diplacanthi, Diplacanthiformes, Eupleurogmus, Euthacanthidae, Gemuendolepis, Haplacanthus, Homacanthus, Ischnacanthiformes, Lupopsyroides, Lupopsyrus, Machaeracanthidae, Monopleurodus, Nodacosta, Nodonchus, Onchus, Parexus, Paucicanthus, Pinnacanthus, Promesacanthus, Ptychodictyon, Seretolepis, Sinacanthus, Striacanthus, Tetanopsyrus, Yealepis
Subtaxa: Atopacanthus Poracanthodes
Ecology: nektonic carnivore
Distribution:
• Devonian of Bolivia (1 collection), Germany (2), the Russian Federation (2)
• Silurian of China (2), Estonia (1)
Total: 8 collections each including a single occurrence