Tetractinelida or Tetractinellida: How To spell?
The word Tetractinelida is misspelled against Tetractinellida, a noun meaning "A division of Spongiae in which the spicules are siliceous and have four branches diverging at right angles. Called also Tetractinellinae."
Tetractinellida has double "ll" is mispronounced as "l"Remember double 'LL' in between the strings tetractine & ida which should not be misspelled with single 'L'
Wrong Spelling:  tetractine-l-ida  Correct Spelling:  tetractine-ll-ida 
Find more wrongly spelled words of Tetractinellida to spell it well.