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Calcaronea

Calcaronea
Matmor calcisponge Peronidella.jpg
Peronidella sp. from the Middle Jurassic of Israel.
Scientific classification
Kingdom: Animalia
Phylum: Porifera
Class: Calcarea
Subclass: Calcaronea
Orders

Baerida
Leucosolenida
Lithonida
Sycettida
Pharetronida


Baerida
Leucosolenida
Lithonida
Sycettida
Pharetronida

Calcaronea is a subclass in the class Calcarea.They are Calcarea with the triactines and the basal system of tetractines sagittal (i.e. the rays of the spicule make unequal angles with each other), exceptionally regular. In ontogeny the first spicules to be secreted are diactines. Choanocytes are apinucleate. Calcaronea have amphiblastula larvae



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Wikipedia

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