Button polyp corals
A close-up of the polyps on a green button coral. They remind me of venus fly traps.
A view of the entire green button polyp colony.
These green button polyps broke loose and started growing in the sand.
Another view of the migratory polyps
Theses are brown button polyps: similar conceptually to the green.
Here you can see the brown button polyp colony next to an atlantic anemone, with the green button polyp colony in the background on the upper right.