Phylum: Porifera

1
Phylum Porifera

• Sponges
• Among the oldest animal fossils (750 million
  years old)
• Filter feeders
• Sessile

2
Anatomy of Porifera
3
Spicules

• The skeleton of sponges
• Can be made of calcium carbonate or silica

4
Phylum Porifera Three Classes
Desmospongiae
Hexactinellida
Calcarea
5
Class Hexactinellida

• Glass sponges
• Skeleton
• made up by silica spicules arranged with six
  sides and collagen.

6
Class Desmospongiae

• Most diverse group
• Skeletons
• Spicules made up of spongin
• Spongin is a type of collagen protein
• Shapes vary from encrusting to branches

7
Class Calcarea

• Diversity is greatest in the tropics
• Skeleton
• Spicules made up of calcium carbonate
• Collagen fibers