Pinipedes or Pinnipedes: How To spell?
The word Pinipedes is misspelled against Pinnipedes, a noun meaning "Same as Steganopodes."
Pinnipedes has double "nn" is mispronounced as "n"Remember double 'NN' in between the strings pi & ipedes which should not be misspelled with single 'N'
Wrong Spelling:  pi-n-ipedes  Correct Spelling:  pi-nn-ipedes 
Find more wrongly spelled words of Pinnipedes to spell it well.