Asterias forbesi Asterias forbesi Asterias forbesi, commonly known as Forbes sea star, is a species of starfish in the family Asteriidae. It is found in shallow waters in the northwest Atlantic Ocean and the Caribbean Sea. "Asterias forbesi" usually has 5 arms but occasionally has 4 or 6. Like many starfish species, the upper surface is covered in blunt conical projections giving it a rough feel. Some of these are pedicellariae, minute pincers that can grip objects. The arms are plump, broad at the base and tapering to a blunt tip. This starfish grows to about in diameter with an arm length
Starfish use their large pedicellariae to capture small fish and crustaceans. There may also be papulae, thin-walled protrusions of the body cavity that reach through the body wall and extend into the surrounding water. These serve a respiratory function. The structures are supported by collagen fibres set at right angles to each other and arranged in a three-dimensional web with the ossicles and papulae in the interstices. This arrangement enables both easy flexion of the arms by the starfish and the rapid onset of stiffness and rigidity required for actions performed under stress. The water vascular system of the starfish is