Characters: Colonies have encrusting bases and irregular branches which seldom fuse. Branching may be open or compact. Coenosteum ridges are very prominent and form a sinuous pattern over branch surfaces. Corallites are deeply embedded between the ridges. The skeletal structure of the corallites is Porites-like, with very elongate septa which occasionally fuse. Colour: Grey or green with pale coenosteum ridges. Similar species: Montipora setosa and M. vietnamensis, both of which may have a similar growth-form but both have relatively superficial corallites without well developed coenosteum ridges. See also M. malampaya. Resembles the poritid Porites negrosensis underwater and corallites of skeletons are unusually Porites-like. Habitat: Shallow protected embayments. Abundance: Rare