hmm - fun one.
There are two colors in there that are definitely not dinos. green and pink.
Green will be either GHA or bryopsis (if you pull bryopsis and lay it in a shallow dish of water, you will see the feather-like structure.)
Pink in the back left corner of the wall is going to be cyano.
there are probably also dinos or diatoms covering the algae, but mostly the algae structure here is GHA would be my guess.
(waves at fellow Mississippian)