Chondrichthyes
 Chondrichthyes (/kɒnˈdrɪkθɨ.iːz/; from Greek χονδρ- chondr- 'cartilage' ἰχθύς ichthys 'fish') or cartilaginous fishes are jawed fish with paired fins paired nares scales a heart with its chambers in series and skeletons made of cartilage rather than bone.