Borers and Grazers
Boreing organisms can be found in every piece of rock
broken from the reef. Predominant among these are the rock boring clams,
Lithophaga nigra, and Spenglaria rostrada,
several species of Polychaetes, endolithic algae and
boring sponges Cliona and Spiponodicyon.
The spiny sea urchin Diadema antillarum grazes the
reef surface. The parrot fish Sparisoma virde and
S. abillgardi as well as other fish also graze the
surface flora, ingest sand from the valleys and occasionally take bites
of hard coral and coralline algae.