Complex sentence: The most widespread and polymorphic species is "Cymbiolacca pulchra" from the Great Barrier Reef which has been extensively divided by taxonomists and is often treated as a number of species.
Split into simpler sentences: The most widespread and polymorphic species is "Cymbiolacca pulchra" from the Great Barrier Reef. This radiation has been extensively divided by taxonomists and is often treated as a number of species.