Both are correct (as opposed to protoconch) but teleoconch is most commonly and widely used than teloconch.

Both are correct (as opposed to protoconch) but teleoconch is most commonly and widely used than teloconch.

Thank you Mauro, I think I will go with 'teleoconch'. But whilst on the topic, what is wrong with 'protoconch'?

The word comes from the greek τελέω (teleo) which means "complete" or "end." So teleoconch is more correct. But it has often been misspelled teloconch, which came into common use.

Okay, always best to go back to the roots of the word. Thank you again.