blastozoa

{{Short description|Subphylum of marine invertebrates}}

{{Automatic taxobox

| fossil_range = {{fossil range|Cambrian|Permian}}

| image = Haeckel Blastoidea.jpg

| image_caption = Blastoids, an example of a single group of blastozoans.

| taxon = Blastozoa

| subdivision_ranks = Classes

| subdivision = * Class Eocrinoidea (Cambrian - Silurian)

• Class Parablastoidea (Ordovician)
• Class Rhombifera (Ordovician - Devonian)
• Class Diploporita (Ordovician - Devonian)
• Class Blastoidea (Ordovician - Permian)
• Class Paracrinoidea (Ordovician-Silurian)

}}

Blastozoa is a subphylum of extinct echinoderms characterized by the presence of specialized respiratory structures and brachiole plates used for feeding.{{cite journal|last1=Sprinkle|first1=J.|title=Morphology and evolution of blastozoan echinoderms|journal=Harvard Special Publication: Museum of Comparative Zoology|date=1973}} It ranged from the Cambrian to the Permian. Biserial, triradiate, and pentaradiate ambulacral patterns have been identified in blastozoa specimens. The pentaradiate pattern in particular has been associated with several different classes.{{Cite journal |last=Bockelie |first=JF |date=1981 |title=SYMMETRY AND AMBULACRAL PATTERN OF THE RHOMBIFERAN SUPERFAMILY CARYOCYSTITIDIA AND THE RELATIONSHIP TO OTHER BLASTOZOA |journal=GEOLOGISKA FORENINGENS {{!}} STOCKHOLM FORHANDLINGAR |volume=103 |issue=4 |pages=491-498 |via=Web of Science}}

A significant species has been found at the Zaouïa Formation.{{citation |last1=Makhlouf |first1=Y. |last2=Lefebvre |first2=B. |last3=Nardin |first3=E. |last4=Nedjari |first4=A. |last5=Paul |first5=C.R.C. |year=2017 |title=The diploporite blastozoan Lepidocalix pulcher from the Middle Ordovician of northern Algeria: Taxonomic revision and palaeoecological implication |url=http://www.app.pan.pl/article/item/app002862016.html |journal=Acta Palaeontologica Polonica |volume=62 |pages=299–310 |doi=10.4202/app.00286.2016 |accessdate=2020-05-29}}