Hey David, can ya spare a moment and learn me something here? I was going to say Protopalythoa but I didn't see the distinctive "slit" for a mouth. Is the slit irrelevant?
I look at many physical cues to make an ID but corals ID's are not really my thing. The picture is very dark but I can see the center of the oral disc. The most telling cues in this picture are color, tentacle shape and solitary polyp.
Not to mention the size of the disk and the thickness of each tenticle.
The slit mouth is a total give away as well if you can see it.
SOme times theywill look as if they have a round mouth but it will look more full or open like they just ate somthing (More than likely theyjus tdid LOL).
Other than parazoanthus (Yellow polyps), and "PALY"thoas (crater polyps)
They are the only polyps you can spot feed meaty foods that are in the zoanthid family (all be them TINY bits of meaty foods).
They will grow twice as fast and get twice as big if you do spot feed them.