Blastozoa

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Blastozoa
Temporal range: Cambrian–Permian
Haeckel Blastoidea.jpg
Blastoids, an example of a single group of blastozoans.
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Subphylum: Blastozoa
Classes

Blastozoa is a subphylum of extinct Echinoderms characterized by the presence of specialized respiratory structures and brachiole plates used for feeding. [1] It ranged from the Cambrian to the Permian.

A significant species has been found at the Zaouïa Formation. [2]

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<span class="mw-page-title-main">Paleozoology</span> Branch of paleontology, paleobiology, or zoology

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Ctenocystoidea is an extinct clade of echinoderms, which lived during the Cambrian and Ordovician periods. Unlike other echinoderms, ctenocystoids had bilateral symmetry, or were only very slightly asymmetrical. They are believed to be one of the earliest-diverging branches of echinoderms, with their bilateral symmetry a trait shared with other deuterostomes. Ctenocystoids were once classified in the taxon Homalozoa, also known as Carpoidea, alongside cinctans, solutes, and stylophorans. Homalozoa is now recognized as a polyphyletic group of echinoderms without radial symmetry. Ctenocystoids were geographically widespread during the Middle Cambrian, with one species surviving into the Late Ordovician.

The Zaouïa Formation, also known as the Zaouïa Schists, is a Middle Ordovician (Darriwilian) geologic formation in Algeria. The formation crops out in the Aïssa Mimoun Massif near Zaouïa of Stita at the confluence of Wadi Stita and Wadi Seba at about 5 kilometres (3.1 mi) northeast of Tizi-Ouzou in the municipality of Makouda, in the Kabylian Mountains of northern Algeria. The type locality is about 29 kilometres (18 mi) away from the Katian outcrops of northern Djurdjura.

References

  1. Sprinkle, J. (1973). "Morphology and evolution of blastozoan echinoderms". Harvard Special Publication: Museum of Comparative Zoology.
  2. Makhlouf, Y.; Lefebvre, B.; Nardin, E.; Nedjari, A.; Paul, C.R.C. (2017), "The diploporite blastozoan Lepidocalix pulcher from the Middle Ordovician of northern Algeria: Taxonomic revision and palaeoecological implication", Acta Palaeontologica Polonica , 62: 299–310, retrieved 2020-05-29