I also believe that there are a number of these
Turbinaria sp. some of which show the polyp extension and some that do not. Not surd which yours is just some more info.
Quote;
"Most Turbinaria spp. (with the exception of T. peltata) do not extend polyps during the day in nature, although in captivity with human-determined feedings, they will adapt to captive life with partial to full daytime extention as a whole for the genus.
T. reniformis has very thin, almost exclusively unifacial plates with widely spaced, flattened bump-like corallites with very small polyps.'
And here you can see some of the variations and their polyp concentrations.
http://www.livestockusa.org/PAGODA.html