Arthropods

• Arthropods (Phylum Arthropoda) make up the largest phylum of animals– 3 out of every 4 animals are arthropods

• The largest group of Arthropods are the insects, which are rare in the sea

• The overwhelming majority of Arthropods in the ocean are crustaceans (class Crustacea)– Shrimp, lobster, crabs, copepods, barnacles

Phylum Arthropoda

• Arthropod means “jointed foot”• Jointed appendages such as legs and

mouthparts• Body is segmented and bilaterally-symmetric• Arthropods possess a tough, external

skeleton, or exoskeleton – Composed of chitin– Secreted by underlying tissue, must molt or shed

Evidence of Arthropoda

segmentation jointed appendages exoskeletonKEY