Phylum Echinodermata Examples

Examples : Antedon (sea lily), Neometra (feather star), Rhizocrinus etc.
ASTERIAS :
Classification:
Phylum ....... Echinodermata -
Class ............Esteroidea –
order...........Forcipulata -
Genus .............Asterias (Sea Star of Starfish)
Coelomate, pentaradiaie and spiny-skinned animals with water vascular system.
Found abundantly on the hard rocky bottoms.
Centraldisc and arms fused.
Forcipulateandpedicellatepedicellariae.
Colour is orange to purple.
lt consists of a central disc and five radial, tapering arms.
Flat lower oral surface bears mouth and ambulacral
grooves in arms while convex upperface is aboral
surface, bears anus and madreporite.
ECHINUS :
Glassification:
Phylum ....... Echinodermata
Gtass ............Echinoifl ea
Order ...........Diadematoidea
Genus .............Echinus (Sea Urchin)
Commonlycalled'Sea-urchin'.
Body globular or rounded with movable spines.
Ten oraltentacles present around mouth.
Masticatoryapparatus'Aristotle's lantern' present.
The pedicellariae and madreporite are present.
Tube feet occur in ten rows.
HOLOTHURIA : (Sea Cucumber)
Classification:
Phylum ....... Echinodermata
Class ............Holothuroidea
Order ...........Dendrochirota
Genus .............Cucumaria
Coelomate, pentaradiate and spiny-skinned animals with water vascular system.
Body orally and aborally elongated.
Oral tentacles tree-like (dendroid).
Commonly called 'Sea-cucumber'.
Cylindrical body is antero-posteriorly elongated.
ANTEDON :
Classification:
Phylum ....... Echinodermata -
Class ............Crinoidea –
Order...........Articulata –
Coelomate, pentaradiate and spiny-skinned animals with watervascular system.
Attachment by aboral stalk, Pedicellariae spines and madreporite absent.
Central disc covered by a movable tegmen having various ossicles.
Food grooves open.
Body oval or spherical and composed of test enclosing viscera.