The differences between Zoas, Paly's, Button Polyps

[porpoiseaquatics]

This may come across as a stupid question from an experienced reefkeeper but honestly, until just now, I've never kept any of the above with success. Now it seems I'm headed in the right direction and have each of these in my tank but I'm not 100% certain.

What are the differences between these? Is it just physical size? Are there other factors that clearly indicates which is which? I've got some button polyps, some teal palys and some fire-n-ice zoas in my tank (these are just the ones that I know) and their basic features all look alike.

 

[superclown]

From what I understand zoanthids and button polyps are the same thing and that palys are pretty close in similarity and that the only major difference between the two is this :

The difference between the Zoanthus (Button Polyps) and the Palythoa (Sea Mat) species is that Button Polyps, although colonial, do not share a common mat. They grow as individuals where the Sea Mats have a fibrous encrusting mat. Individuals of the Palythoa species can not be separated without cutting through this fibrous mat. Most Palythoa are sold as Button Polyps as the two species are very similar.