Subclass Calcaronea
Order Lithonida

taken from 'Sponguide' by J.N.A. Hooper (Queensland Museum, Brisbane)

Definition: Generally restricted to shaded habitats such as caves and tunnels; massive reinforced calcitic (hypercalcified) skeleton, together with tuning fork spicules and saggital tetractines as free spicules; larvae are amphiblastula; choanocytes are apinucleate.

With 3 families (see menu left).

PDF Version of the Calcarea Chapter