Echinozoa

Echinozoa
The melon sea urchin (Echinus melo) in northwest Sardinia
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Subphylum:	Echinozoa
Classes
Echinoidea or sea urchins Holothuroidea or sea cucumbers Ophiocistioidea † Helicoplacoidea † ?Arkarua † † = Extinct

† = Extinct

Echinozoa is a subphylum of free-living echinoderms in which the body is essentially globoid with meridional symmetry. Echinozoans lack arms, brachioles, or other appendages, and do not at any time exhibit pinnate structure.

List of echinodermata orders.

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