ical ▁sc ute ▁present ; ▁verte br al ▁sc utes ▁wider ▁than ▁ple ur als ; ▁verte br al ▁ 3 – 4 ▁sul cus ▁on ▁neural ▁ 6 ; ▁reduced ▁cle ith rum ▁present ; ▁arrow - sh aped ▁ent op las tr on ▁that ▁does ▁not ▁separate ▁the ▁e pi pl ast ra ▁anterior ly ; ▁one ▁pair ▁of ▁mes op last ra ▁that ▁meet ▁med ial ly ; ▁one ▁small ▁pair ▁of ▁ext rag ular s ▁present ; ▁and ▁anal ▁sc ute ▁that ▁does ▁not ▁reach ▁the ▁hyp op las tr on . ▁ ▁Classification ▁E ile anch ely s ▁is ▁a ▁stable ▁tax on , ▁which ▁means ▁that ▁its ▁classification ▁does ▁not ▁differ ▁much ▁in ▁cl ad og rams . ▁It ▁is ▁related ▁to ▁both ▁He ck ero ch ely s ▁and ▁Kay ent ach ely s , ▁although ▁often ▁it ▁is ▁found ▁to ▁be ▁derived ▁from ▁the ▁later . ▁The ▁below ▁cl ad ogram ▁illustr ates ▁the ▁relationships ▁of ▁bas al ▁test ud in ata : ▁ ▁Pale o ec ology ▁ ▁Hab itat ▁E ile anch ely s ▁lived ▁in ▁the ▁Kil mal u ag ▁Form ation , ▁which ▁has ▁a ▁Late ▁B athon ian ▁age . ▁The ▁formation ▁is ▁made ▁up ▁entirely ▁of ▁mud stone , ▁sh ale ▁and ▁some ▁lim estone , ▁and , ▁as ▁many ▁aqu atic ▁types ▁of ▁animals ▁have ▁been ▁found ▁in ▁it ▁and ▁land ▁verte br ates ▁are ▁rare , ▁it ▁was ▁almost ▁certainly ▁marine . ▁Therefore , ▁E ile anch