▁sau rop od ▁foss il ▁to ▁be ▁scientific ally ▁described ▁was ▁a ▁single ▁to oth ▁known ▁by ▁the ▁non - Lin na e an ▁des criptor ▁R ut ell um ▁imp lic atum . ▁This ▁foss il ▁was ▁described ▁by ▁Edward ▁L hu yd ▁in ▁ 1 6 9 9 , ▁but ▁was ▁not ▁recognized ▁as ▁a ▁giant ▁pre histor ic ▁re pt ile ▁at ▁the ▁time . ▁Din osa urs ▁would ▁not ▁be ▁recognized ▁as ▁a ▁group ▁until ▁over ▁a ▁century ▁later . ▁ ▁Richard ▁O wen ▁published ▁the ▁first ▁modern ▁scientific ▁descri ptions ▁of ▁sau rop ods ▁in ▁ 1 8 4 1 , ▁in ▁a ▁book ▁and ▁a ▁paper ▁naming ▁Card iod on ▁and ▁Cet ios aur us . ▁Card iod on ▁was ▁known ▁only ▁from ▁two ▁unusual , ▁heart - sh aped ▁teeth ▁( from ▁which ▁it ▁got ▁its ▁name ), ▁which ▁could ▁not ▁be ▁identified ▁beyond ▁the ▁fact ▁that ▁they ▁came ▁from ▁a ▁previously ▁unknown ▁large ▁re pt ile . ▁Cet ios aur us ▁was ▁known ▁from ▁slightly ▁better , ▁but ▁still ▁scra ppy ▁remains . ▁O wen ▁thought ▁at ▁the ▁time ▁that ▁Cet ios aur us ▁was ▁a ▁giant ▁marine ▁re pt ile ▁related ▁to ▁modern ▁cro cod iles , ▁hence ▁its ▁name , ▁which ▁means ▁" wh ale ▁l izard ". ▁A ▁year ▁later , ▁when ▁O wen ▁co ined ▁the ▁name ▁Din osa uria , ▁he ▁did ▁not ▁include ▁Cet ios aur us ▁and ▁Card iod on ▁in ▁that ▁group . ▁ ▁In ▁ 1