Chondrichthyes - Phylogeny

Phylogeny

Subphylum Vertebrata └─Infraphylum Gnathostomata ├─Class Placodermi — extinct (armored gnathostomes) └Microphylum Eugnathostomata (true jawed vertebrates) ├─Class Chondrichthyes (cartilaginous fish) └─(unranked) Teleostomi (Acanthodii & Osteichthyes) ├─Class Acanthodii — extinct ("spiny sharks") └Superclass Osteichthyes (bony fish) ├─Class Actinopterygii (ray-finned fish) └─Class Sarcopterygii (lobe-finned fish) Note: lines show evolutionary relationships.