1. Arthropods are a phylum of joint-legged invertebrate animals including insects, arachnids, crustaceans and others. 2. They have segmented bodies, jointed appendages, a hard exoskeleton and molt to grow. 3. Major groups include insects, arachnids like spiders and scorpions, crustaceans like crabs and lobsters, and extinct trilobites.

1. Gk. “arthros” – joint + “podos” – foot ARTHROPODA

2. VARIETY

3. Hermit Crab Fairy Shrimp Centipede Horseshoe Crab

5. Size Color Shape Method of Movement

6. Jointed Legs Exoskeleton Segmented Body Distinct Head Compound Eyes (most cases)

7. Common throughout marine, freshwater, terrestrial, and even aerial environments GENERAL CHARACTERISTICS

8. Characteristics of Arthropods Segmented Jointed appendages Hard external skeleton 3 parts-head, thorax, abdomen (arachnids exception) Exoskeleton-hard, external skeleton made of chitin Molting- shed old exoskeleton and secrete a larger one, very vulnerable after molting

9. Complete digestive tract ( mandible -chewing or proboscis - sucking) with a dorsal heart and a ventral nervous system Respiration through gills, trachea, book lungs or body surface Sensory organs include antennae and hairs, simple and compound eye Reproduces (mostly sexually), one to several larval stage

10. The muscle system is more or less assisted by hydraulics originated from the blood pressure created by the heart Respiration through gills, trachea, book lungs or body surface With open circulatory system. Haemolymph that contains haemocyanin , a copper-based oxygen-carrying protein

11. Body parts Ganglia -clusters of nerve cells along a nerve cord Compound eyes -may facets each with their own lenses, some have single lenses and some have both Spiracles-holes in the exoskeleton that allow gas exchange (book lungs in arachnids) Trachea -chitin lined tubes in spiracles

12. Four SUBPHYLA of Arthropods Trilobita – thought to be the oldest arthropods Chelicerata – two part body and mouthparts called chelicerae Crustacea – hard exoskeleton, two pairs of antennae, mouthparts called mandibles Uniramia – contains more species than all other groups of animals alive today

13. SUBPHYLUM - Trilobites CLASS TRILOBITA – Trilobites SUBPHYLUM CHELICERATA CLASS ARACHNIDA – Spiders, Scorpions, Ticks CLASS MEROSTOMATA – Horseshoe crabs CLASS PYCNOGONIDA – Sea spiders REPRESENTATIVE ORGANISMS:

14. SUBPHYLUM UNIRAMIA CLASS CHILOPODA – Centipedes CLASS DIPLOPODA - Millipedes CLASS INSECTA – Insects Class Branchiopoda – Brine shrimp

15. CLASS CEPHALOCARIDA – Horseshoe shrimp CLASS MAXILLOPODA – Barnacles, and Fish lice CLASS MALACOSTRATA – Lobsters, Crabs, and Shrimps

16. CLASS CRUSTACEA Lobsters, Crabs and Shrimps American lobster Homanus americanus Blue crab Callinectes sapidus

17. CLASS INSECTA Ants, Beetles and Bugs ORDER HYMENOPTERA Fire ant Solenopsis invicta ORDER ORTHOPTERA Migrating locust Locusta migratoria ORDER COLEOPTERA Weevil Beetle

18. MAJOR PARTS OF AN INSECT

19. Insects that have piercing and sucking mouthparts are called BUGS while BEETLES are insects distinguished as those having forewings modified into hard wing cases that cover and protect the hind wings and abdomen!

20. CLASS ARACHNIDA Spiders, Ticks and Scorpions Wolf spider Lycosa tarentula

21. The Goliath Bird-eating tarantula ( Theraphosa blondi) But can grow as much as 1 ft in diameter!

22. CLASS MEROSTOMATA Horseshoe crabs

23. CLASS CHILOPODA Centipedes Peruvian Giant

24. CLASS DIPLOPODA Millipedes Harpaphe haydeniana

25. CLASS TRILOBITA Trilobites

26. LIFE CYCLES OF SOME INSECTS

27. LIFE CYCLE OF A DRAGONFLY (CLASS INSECTA ORDER ODONATA)

28. LIFE CYCLE OF A FRUIT FLY (CLASS INSECTA ORDER DIPTERA)

29. LIFE CYCLE OF A BUTTERFLY (CLASS INSECTA ORDER LEPIDOPTERA) (Larva) Caterpillar (Pupa) Chrysalis

30. LIFE CYCLE OF A GRASSHOPPER (CLASS INSECTA ORDER ORTHOPTERA)

31. MIMICRY AND CAMOUFLAGE Mimicry - take on the appearance of (another animal or plant) in order to deter predators Camouflage - the natural coloring or form of an animal which enables it to blend in with its surroundings

32. ECOLOGICAL IMPORTANCE Serve as food source for both animals and humans Aid in the propagation of plant species by means of cross-pollination Control the population of some harmful organisms Some act as scavengers or saprotrophs