The Cushion Stars and Allies contains 29 genera and 263 species of sea stars, around one sixth of the known species of sea stars.
Many species within this large family are traditional sea stars, usually with 5 arms surrounding a thick, brightly coloured body with a central 'dome' which can often look as though it has been inflated.
The upper surface of Cushion Stars can be granular, spiny or smooth. They have rows of tube feet on their lower side which are located within a v-shaped groove and are used for movement. These tube feed may be sucker-tipped or pointed.
The gut of a starfish occupies most of the disc and extends into the arms. The mouth is located at the centre of the lower surface, feeding mostly on bottom-dwelling invertebrates.
Most sea stars can regenerate lost arms or damaged parts and they can shed arms as a means of defence.
Although starfish do not have much in the way of sense organs, they are sensitive to touch, light, temperature, orientation and the status of the water around them. The tube feet, particularly those at the tips of the arms, are able to sense odour sources such as food.
2 species found on this page.
