a herring diplomystus and a stingray heliobatis radians foss

adpression age aged ancient animals authigenic bioimmuration bones carbonization casts clupeiformes clupeomorph dasyatidae deceased diplomystus evolution evolutionary exoskeletons extinct family fish fossil fossilization genus geological heliobatis herring history impression imprints living mineralization mineralized molds myliobatiformes natural once organism paleontology past permineralization petrified preserved radians ray recrystalization remains replacement sardine shells stingray stone trace