"The colonies of Cladiella pachyclados are like many other soft coral, they are soft and commonly firm, fleshy and several stout lobed form which gives a lumpy appearance. The colonies are relatively insignificant and have a restricted polyp contraction control (Fabricius & Alderslade 2001). They possess a small but very distinctive stalk at the base that attaches the coral to rocks. The polyparium of the colony, which is the supporting framework of the coral, are divided into many short, rounded knob-like bump (Fabricius & Alderslade 2001). The stalk of this coral is generally white, grey or pale brown in color when the polyps are contracted.
However when the polyps are expanded, the colony will be brown or greenish due to the dense concentration of zooxanthellae in the polyps.
The quick retraction of polyps when disturbance occurs causes an instantaneous color change from brown to white. This is one of the interesting characteristic of the coral which also gives rise to its common name, the blushing coral (Fabricius & Alderslade 2001)."
Invertebraten of the Coral Sea
Jenn Yee Chan (2013)