Calcareous Sponge - Classification

Classification

Of the 15,000 or so species of Porifera that exist, only 400 of those are Calcareans.

Calcarean sponges first appeared during the Cambrian and their diversity was greatest during the Cretaceous period. Recent molecular analysis suggests that the class Calcarea should be designated as a phylum, in particular the first to have diverged in the Kingdom Animalia; the other sponges belong to the phylum Silicarea.

The calcareous sponges are divided into two subclasses and seven orders:

Class Calcarea

• Subclass Calcinea
  • Order Clathrinida
  • Order Leucettida
  • Order Murrayonida
• Subclass Calcaronea
  • Order Baerida
  • Order Leucosolenida
  • Order Lithonida
  • Order Sycettida