marine invertebrates

Meet the Lower InvertebratesKingdom-Animalia

Major Invertebrate Phyla

1) Phylum Porifera

2) Phylum Ctenophora

3) Phylum Cnidaria

4) Phylum Platyhelminthes

5) Phylum Annelida

6) Phylum Mollusca

7) Phylum Echinodermata

8) Phylum Arthropoda

Symmetry

1) Phylum Porifera

-Example: Sponges

-Named for many pores

-No symmetry (asymmetrical)

-Most primitive (simple) animals – no organs

2) Phylum Ctenophora

-Example: Comb jellies

-Radial symmetry

-Harmless bioluminescent jellies

3) Phylum Cnidaria-Jellyfish (AKA Sea Jellies), sea anemones, and corals

-Members of this group have stinging cells

-Radially symmetrical

-2 tissue layers

-No organs

4) Phylum Platyhelminthes-The Flatworms

-Bilateral symmetry

-Simple

5) Phylum Annelida

-The Segmented Worms

-Examples-Polychaetes

(and Earthworms on land)

-Bilateral Symmetry

-Advanced worms

6) Phylum Mollusca

-Examples: Clams, snails, octopus, squid

-Soft bodied animals with a large “foot”

-Bilateral symmetry

7) Phylum Arthropoda

-Examples: Crabs, lobsters, barnacles, insects, arachnids

-Exoskeleton

-Jointed or hinged appendages

-Bilateral symmetry

8) Phylum Echinodermata

8) Phylum Echinodermata

-Examples: Sea stars, sea urchins, sand dollars, sea cucumbers

-Bumpy skinned animals

-Pentamerous radial symmetry