Chondropterygi or Chondropterygii: How To spell?
The word Chondropterygi is misspelled against Chondropterygii, a noun meaning "A group of fishes, characterized by cartilaginous fins and skeleton. It includes both ganoids (sturgeons, etc.) and selachians (sharks), but is now often restricted to the latter."
Chondropterygii has double 'ii' in the end mispronounced as 'i'Remember double 'II' appears in the end of this word which should not be misspelled with single 'I'
Wrong Spelling:  chondropteryg-i  Correct Spelling:  chondropteryg-ii 
Find more incorrect spellings of Chondropterygii to spell right way.