Another photo of the cushion sea star (Oreaster reticulatus) scooting along in about a foot of water near Munyon Island in the Lake Worth Lagoon estuary. The lighter colored round feature at lower center is called a madreporite. It acts like a pressure equalizing valve and filters seawater into the sea star's water vascular system. These beauties are protected under Florida law. en.wikipedia.org/wiki/Madreporite
785