The document describes the characteristics of arthropods. It notes they have a chitinous exoskeleton, jointed appendages, undergo molting as they grow, and have an open circulatory system. It then describes the main types of arthropods - arachnids, crustaceans, chilopods, diplopods, and insects. For each type, it provides 1-2 defining physical characteristics.

1. ARTHROPODS
“Jointed-legs”

2. ARTHROPODS
 Chitinous exoskeleton
 Paired of jointed appendages
 Growth accompanied by ecdysis or molting
 Open circulatory system
 Ventral nervous system
 Complete digestive tract
 Metamorphosis

3. TYPES OF ARTHROPODS
 Arachnids
 Crustaceans
 Chilopods
 Diplopods
 Insects

4. ARACHNIDS
The female black widow is one of
the most poisonous creatures with
venom more potent than coral
snakes, cobras or rattlesnakes.
However her bite is rarely fatal in
humans. Why not?
Black Widow

5. ARACHNIDS
 Eight pairs of appendages
 Lack antennae
 Lack mandibles
 Divided into prosoma (cephalothorax) and opisthosoma
(abdomen)
 Gas exchange through book gills

7. BOOK GILLS

8. CRUSTACEANS

9. CRUSTACEANS
 The head has two compound eyes, two pairs of antennae, and
three pairs of mouthparts.
 A pair of green glands excrete wastes near the base of antennae.
 The abdominal segments have swimmerets (swimming legs)

10.  The sexes are separate. Eggs are attached to the swimmerets
(swimming legs) of the female. The first pair is enlarged in the
male (it is used to pass sperm to the female).
 The tail is fan-shaped, and ends in uropods and a telson.
 Open circulatory system
 Ventral nervous system

11. CHILOPODS

12. CENTIPEDES
 1 pair of legs per body segment
 1 pair of poison claws/fangs underneath the head
 Antennae present
 Simple eyes
 Carnivorous

13. DIPLOPODS
 2 pairs of legs per body segment, although some juveniles may
posses only 1 pair per segment
 Simple eyes if present, although many have no eyes
 1 pair of antennae
 Chewing mouthparts
 Herbivores and Scavengers

14. MILLIPEDES

15. INSECTS
 A body divided into three parts (head, thorax and abdomen)
 Three pairs of legs
 Usually one pair of antennae and a pair of compound eyes (a
few exceptions to these characteristics are found)
 Usually two pairs of wings (absent in many insects such as lice,
fleas, ants; flies have one pair of wings)

16. INSECTS
 A body divided into three parts (head, thorax and abdomen)
 Three pairs of legs
 Usually one pair of antennae and a pair of compound eyes (a
few exceptions to these characteristics are found)
 Usually two pairs of wings (absent in many insects such as lice,
fleas, ants; flies have one pair of wings)

17. INSECT

18. Hydrena ateneo
Source: http://www.philstar.com/headlines/2013/09/08/1185551/new-beetlespecies-found-ateneo-campus

19. SOURCE
 http://www.ento.csiro.au/