Leafy coral, Galaxea astreata.  Huge areas of the floor of Peros Banhos were carpeted with this species below about 30 m deep.  It is an agressive species, which easily kills other corals which try and grow near it.  As a result, these coral carpets consisted almost entirely of this one species.  This dominant characteristic has since been noted in other regions such as East Africa too.  Peros Banhos lagoon, 1978.
