1. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish Protostomes - Lophotrochozoans

2. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish Protostomes - Lophotrochozoans

3. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms

4. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms Cephalization: eyespots and auricles Gastrovascular cavity convoluted gut Ameobocytes

5. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms Parasitic forms: Flukes Asexual reproduction – population increase!

6. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms Parasitic forms: Tapeworm

7. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms Polychaete worms Oligochaete (‘earth’) worms Leeches

8. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms Body cavity (coelom) Hydrostatic ‘skeleton’ Complete gut (‘tract’) Cephalization Segmentation

9. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods

10. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods

11. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods Earliest mollusc, from the Burgess shale, dating to 560 mya, just before the Cambrian Radiation. It is a soft-bodied mollusc

12. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods The ancestral state is segmentation as in the chitons. In the rest of the group there is reduction of sementation.

13. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods The ancestral state is segmentation, as in the chitons. In the rest of the group there is reduction of segmentation.

14. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods The pretty nudibranchs!!

15. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods In sessile bivalves, there has been ‘decephalization’ – loss of head

16. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods In sessile bivalves, there has been ‘decephalization’ – loss of head Scallop eyes

17. 5. Major “Invertebrate” Phyla a. Porifera: Sponges b. Cnidaria: Corals, Hydra, Anemones, Jellyfish c. Platyhelminthes: Flatworms d. Annelida: Segmented worms e. Mollusca: Chitons, snails, bivalves, cephalopods In cephalopods, the shell is reduced from external to internal bony to internal cartilaginous to gone

18. Folded front to back