1. 9. Arthropods
Largest and most successful phylum in the animal kingdom. 85% of all animals!
Exoskeleton made of Chitin (light/hard polysaccharide).
Jointed Appendages.
Cephalization-compound eyes, ocelli (eyespots), antennae.

3. SUBPHYLUM CHELICERATE
Fang-like mouthparts (Chelicerae)-Pedipalps for sense. 2 Classes.
Class Merostomata-Horseshoe crabs.
Class Arachnids-8 legs
2 body parts-spiders, ticks, mites, scorpions.
Book lungs/gills

4. Horseshoe Crab
1. Carapace
2. Telson
3. Compound eye
4. Anterior spine

5. ARACHNIDS
Spiders
Scorpions
Ticks

6. SUBPHYLUM MANDIBULATES
Antennae, Mandibles & Maxillae
Includes 4 classes-Crustacea, Diplopoda, Chilopoda & Insecta.
Crustaceans-add some limestone to the chitinous exoskeleton.
Lobsters & crabs are the giants of this group-most are a few centimeters long.

7. Crustaceans
In addition to lobsters & crabs, shrimp, copepods and barnacles all belong to this class.
Due to the nature of their rigid exoskeleton, crustaceans must “molt” or shed their shell in order to grow.
They use an enzyme to split their shell & then crawl out.

9. MILLIPEDES & CENTIPEDES
Class Diplopoda-The millipedes only have about 100 legs with 2 pairs-legs/segment
Class Chilopoda-The centipedes have fewer legs (1 pair/segment).
While millipedes scavenge on decaying plant material, centipedes are predators w/venom glands.

10. CLASS INSECTA Class Insecta-largest group of animals in the world!
3 Body parts-Head, Thorax & Abdomen
6 legs, Antennae, Mandibles
Malpighian tubules (Kidneys) get rid of their wastes.

11. INSECT ANATOMY

12. METAMORPHOSIS
One last reason for arthropod success is their ability to go through stages that exploit different food at different times in their life.
Incomplete Metamorphosis-Egg-Nymph-Adult. The nymph stage is like a miniature form of the adult.
Complete Metamorphosis-Egg-Larvae-Pupae-Adult.