Plesiosourian or Plesiosaurian: How To spell?

The word Plesiosourian is misspelled against Plesiosaurian, a noun meaning "A plesiosaur."

Word contains consecutive vowels 'AU' in between alphabets plesios & rian is misspelled as 'OU'
Wrong Spelling:  plesios-ou-rian 
Correct Spelling:  plesios-au-rian 
Check more misspelled words of Plesiosaurian to spell it correct.

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