Plesiosaria or Plesiosauria: How To spell?
The word Plesiosaria is misspelled against Plesiosauria, a noun meaning "An extinct order of Mesozoic marine reptiles including the genera Plesiosaurus, and allied forms; -- called also Sauropterygia."
Word contains consecutive vowels 'AU' in between alphabets plesios & ria is misspelled as 'A' as letter 'U' is phonetically ignWrong Spelling:  plesios-a-ria  Correct Spelling:  plesios-au-ria 
Find more incorrect spellings of Plesiosauria to spell right way.