Articulata (Crinoidea)

Comatulida is an order of crinoids. Members of this order are known as feather stars and mostly do not have a stalk as adults. The oral surface with the mouth is facing upwards and is surrounded by five, often divided rays with feathery pinnules. Comatulids live on the seabed and on reefs in tropical and temperate waters.

subclass of echinoderms

Isocrinida is an order of sea lilies which contains four families.

Cyrtocrinida is an order of sea lilies which contains two suborders and three families.

Bourgueticrinida is an order of crinoids that typically live deep in the ocean. Members of this order are attached to the seabed by a slender stalk and are known as sea lilies. While other groups of crinoids flourished during the Permian, bourgueticrinids along with other extant orders did not appear until the Triassic, following a mass extinction event in which nearly all crinoids died out.

Millericrinida is an order of articulate crinoids that originated in the Anisian (Middle Triassic).