Tubastraea faulkneri with retracted polyps

I have several Tubastraea pictures and I am trying to find the differences between eg. T. coccinea and T. faulkneri.Finally I could find some information here:
https://reefs.com/magazine/field-guide-sun-corals/
The funniest thing is that the first picture in this article is mine and seems to have been taken from Project Noah. I have contacted the author to correct my name which is not correctly spelled. I will retrieve this pic from my archives to also add the species here, I made it in Galapagos quite some years ago. Anyway, other article that has been helpful to see sp differences is this otehr one: https://reefbuilders.com/2012/10/18/tubastraea-faulkneri-coccinea/