Question: true fish as per the biological system of classification
Answer: Fish Fossil range : Mid Cambrian -- Recent PreЄ Є Pg Giant grouper swimming among schools of other fish Head - on view of a red lionfish Scientific classification Kingdom : Animalia Phylum : Chordata ( unranked ) Craniata Included groups Jawless fish † Armoured fish Cartilaginous fish Ray - finned fish ( inc .