Blastozoa

Blastozoa
blastoids
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Subphylum:	Blastozoa
Classes
Class Eocrinoidea (Cambrian - Silurian) Class Parablastoidea (Ordovician) Class Rhombifera = Cystoidea, part (Ordovician - Devonian) Class Diploporita = Cystoidea, part (Ordovician - Devonian) Class Blastoidea (Ordovician - Permian)

Blastozoa is a subphylum of extinct animals belonging to Phylum Echinodermata. This subphylum is characterized by the presence of hydrospires, which are small folds under the lancet plates. See also List of echinodermata orders.

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