3 Main Classes of Phylum Porifera
The following points highlight the three main classes of Phylum Porifera. The three classes are: 1. Calcarea or Calcispongiae— (Calcareous Sponges) 2. Hexactinellida or Triaxonida or Hyalospongiae—(Glass Sponge) 3. Demospongiae. Phylum Porifera: Class # 1. Calcarea or Calcispongiae— (Calcareous Sponges): [Calcarea, L. Calcarious = limy, Calcispongiae, L. Calcis = genitive of calx = lime or chalk] Features: (i) Exclusively marine, [...]