The crinoid Comatula sp. is characterized by its numerous arms with a purple base and can be found in the indo-pacific ocean where the pictures were taken by Heinz Mahler. The feathery arms, which can reach up to 30 cm, are used to catch plankton. In the process the caught plankton is being moved through a system of cirri towards the mouth, which is located at the upper side of the animal.
Feather stars can - apart from very few exceptions - not be kept in a typical reef tank. Even the husbandry in a dedicated filter feeder tank is often accompanied by serious problems and losses.