Complex sentence: The sabre-toothed blenny "Aspidontus taeniatus" is a blenny than mimics the cleaner wrasse but instead of providing a useful cleaning service bites off pieces of healthy skin and scales from the host before darting away to safety.
Split into simpler sentences: The sabre-toothed blenny "Aspidontus taeniatus" is a blenny that mimics the cleaner wrasse. Instead of providing a useful cleaning service however, it bites off pieces of healthy skin and scales from the host before darting away to safety.