List of echinoderm orders

This List of echinoderm orders concerns the various classes and orders into which taxonomists categorize the roughly 7000 extant species[1] as well as the extinct species of the exclusively marine phylum Echinodermata.

A brittle star, Ophionereis reticulata
A sea cucumber from Malaysia
Starfish exhibit a wide range of colours

Subphylum CrinozoaEdit

Class CrinoideaEdit


Haeckel Cystoidea

Class ParacrinoideaEdit

No orders, 13 to 15 genera are known.

Doubtful paracrinoids:

  • Columbocystis
  • Foerstecystis
  • Springerocystis
  • Ulrichocystis
  • Paleocystites
  • Allocystites

Class CystoideaEdit

Class EdrioasteroideaEdit

Subphylum AsterozoaEdit

Class Ophiuroidea (Brittle stars)Edit

Class Asteroidea (Starfish)Edit

Subphylum EchinozoaEdit

Class Echinoidea (Sea urchins)Edit

Strongylocentrotus purpuratus, a well-armoured sea urchin

Class Holothuroidea (Sea cucumbers)Edit

Class OphiocistioideaEdit

No orders recognized: class is divided up into four families, Eucladiidae, Sollasiniidae, Volchoviidae, and Rhenosquamidae. The inclusion of Rhenosquamidae within Ophiocistioidea is doubtful, as the organs identified in fossils of Rhenosquamus as the characteristic "scaly podia" otherwise diagnostic of ophiocistioids may not, in fact, be such structures.

Class HelicoplacoideaEdit

No known orders, 2 known species, Helicoplacus curtisi and H. guthi

Subphylum BlastozoaEdit

Class BlastoideaEdit

Class EocrinoideaEdit

Subphylum Homostelea / HomalozoaEdit

Class CtenocystoideaEdit

Class SolutaEdit

Class CinctaEdit

Class StylophoraEdit


  1. ^ "Animal Diversity Web - Echinodermata". University of Michigan Museum of Zoology. Retrieved 26 August 2012.
  2. ^ Sweet, Elizabeth (2005-11-22). "Asterozoa: Fossil groups: SciComms 05-06: Earth Sciences". University of Bristol. Archived from the original on 2007-07-14. Retrieved 2008-05-07.