1. Phylum Arthropoda
“jointed foot”

2. What is an Arthropod?
An invertebrate with an exoskeleton, jointed appendages and a body that is divided into sections.
Ex. Crustaceans(crabs, lobsters and shrimp)
Insects
Arachnids (spiders, ticks and scorpions)
Centipedes and Millipedes

3. Body Sections of Arthropods
Head or carapace
May be fused as one piece: Cephalothorax
Thorax
Abdomen

4. Basic Characteristics of Arthropods
Bilateral symmetry
Coelom with organ systems
Localized brain and nervous system
Segmented body
Exoskeleton made of protein called chitin
-- Exoskeleton range from hard to waxy

5. Groups/Classes of Arthropods
Arthropods are classified based on the number and structure of their body segments and appendages, particularly mouthparts

6. 1. Crustaceans Primarily aquatic 2 pair of antenna
2 or 3 body segments
Chewing mouthparts called Mandibles
2 main groups:
Decapods (10 legs): Crabs, lobsters, shrimp
Barnacles

8. 2. Arachnids (Spiders and relatives)
2 body sections (cephalothorax and abdomen)
4 pair of walking legs
Most lack antenna
Fang-like mouthparts called chelicera
2 main groups:
Horseshoe crabs
Spiders, ticks and scorpions (arachnids)

9. Horseshoe Crabs

10. Spiders Largest group of arachnids Contain spinnerets (Web makers)
Fang-like chelicera with associated venom glands
External digestion of food
Liquefied food sucked in with pumping stomach
Females may have bright colors/patterns on abdomen (ventral surface)

11. Female Patterns

12. Chelicera

13. Brown Recluse

14. Spider Bite—Day Three

15. Spider Bite—Day Five

16. Spider Bite—Day Six

17. Spider Bite– Day 9

18. Spider Bite– Day 10

19. Mites and Ticks Small in size Parasitic Needle-like chelicera
Liquid diet (blood)
May transmit disease
Ex. Lyme disease transferred by deer tick to humans and other animals

20. Deer Tick
Ixodus dammini

21. Human Parasitic Mites Itch Mite Sarcoptes scabiei
burrows into skin, between fingers, wrists, buttocks, groin etc…
transferred by close
contact with infected human
causes an itchy rash

22. Follicle Mite
Demodex folliculorum
found in the follicles of facial hair
transmitted through close
human contact
mouthparts pierce skin and feed on skin cells or oil from sweat glands
usually no symptoms

23. Scorpions Found in warm climates Claw-like appendages
Venomous stinger on abdomen= aculeus
Chew food with mandibles

24. Arizona Bark Scorpion
Only deadly scorpion in the United States

25. 3. Insects

26. Basic Facts about Insects
3 body segments
3 pair of legs
May have one pair of antenna
Compound eyes (multiple lenses)
2 pair of wings (+ or -)
Breathing tubes in abdomen (spiracles)

27. Sensory Adaptations Eyes Chemical receptors Sensory hairs Ears
Detect color change and movement
Chemical receptors
On mouth, antenna and legs
Sensory hairs
Sense changes in environment, usually movement
Ears
Thin, vibrating membrane = tympanum
Usually found on legs

28. Feeding Adaptations
Chewing mouthparts
Needle-like
Sponge like

29. Common Insect Parasites
Head Louse
Pediculus capitis
Found on human hair and scalp
Transferred through hair to hair contact with infected human
Feed on blood of scalp and hair follicle

30. Crab Louse
Pthirus pubis
Found in human pubic region & may infest facial or armpit hair
Transmitted through sexual contact or close social contact
Causes itching and spots on skin

31. Insect Metamorphosis Process of changing shape or form Two Main Types:
Incomplete
Complete

32. Incomplete Metamorphosis
Larva looks like the adult, only smaller
Ex. some types of beetles, grasshoppers and crickets

33. Complete Metamorphosis
Larva looks completely different than adult
Dormant, pupa stage
Ex. Butterfly, housefly, ladybug, darkling beetle