The beautiful and hardy stoney coral, Montipora undata. This coral is the beauty that gets little attention these days but was very popular several years ago. It was believed to be an encrusting type of stoney coral and I still frequently see it advertised as such. In my experience it can develop plating characteristics and nodules when captive grown fragments are grown under artificial light and sea water. This occurs if conditions favor this formation. Water quality, amount of flow, level of light, along with other environmental ques dictate formation and shape. Mature colonies will form plates and look similar to the species Montipora capricornis in certain instances. The contrasting polyps stay open during the lighted photo-period and you have to love the fat purple active growth rim. I may be partial, but I still rate this stoney coral as a must have for any collector and it is hardy enough to fit the bill for beginners trying there hand at reef building corals.