The Valvatida are an order of starfish in the class Asteroidea, which contains 695 species in 172 genera in 17 families.
Articulata are a subclass or superorder within the class Crinoidea, including all living crinoid species. They are commonly known as sea lilies or feather stars. The Articulata are differentiated from the extinct subclasses by their lack of an anal plate in the adult stage and the presence of an entoneural system. Articulata first appeared in the fossil record during the Triassic period although other, now extinct crinoid groups, originated in the Ordovician.
Comasteridae is a family of crinoids.
Henricia is a large genus of slender-armed sea stars belonging to the family Echinasteridae. It contains about fifty species.
Spatangus is a genus of heart urchins in the Spatangidae family. The genus is synonymous with the previously recognised genera Prospatangus Lambert, 1902 and Spatagus. There are nine recognised species. The type species is Spatangus purpureus Müller, 1776 by subsequent designation.
Antedonidae is a family of crinoids or feather stars in the phylum Echinodermata. Members of the family are unstalked and have ten feathery arms. They can move about freely and have clawed cirri to attach them temporarily to structures.
Charitometridae is a family of crinoids or feather stars in the phylum Echinodermata.
Davidaster is a genus of crinoids. According to the World Register of Marine Species, a number of species that originally were included in the genus Nemaster are now included in Davidaster. Members of this genus have wedge-shaped arms, except for the basal ones, often longer than they are wide. The mouth is off centre and there are no pinnule combs after pinnule 3. The primary comb has the teeth widely separated and confluent with the lateral edge of the segment.
Comaster is a genus of crinoids.
Oxycomanthus is a genus of crinoids belonging to the family Comatulidae.
The feathery sea pen is a species of sea pen in the family Virgulariidae.
The elegant feather star is a species of crinoid in the family Tropiometridae.
The crinoid shrimp, or feather star shrimpHippolyte catagrapha, is a species of shrimp in the family Hippolytidae
Comatulidae is a family of comatulid crinoids. Since 2015, it replaces the family Comasteridae.
Parechinus angulosus, the Cape urchin, is a sea urchin in the family Parechinidae endemic to southern Africa. It is the only species in the genus Parechinus.
Dichrometra is a genus of echinoderms belonging to the family Mariametridae.
Clarkcomanthus is a genus of echinoderms belonging to the family Comatulidae.
Prionocidaris is a genus of echinoderms belonging to the family Cidaridae.
