1. ARTHRPPODS What is Entomology? The study of insects
Chapter 24
What is Entomology?
The study of insects
(and their near relatives).

2. Review of Zoological Nomenclature
Taxonomic Categories
Kingdom - Animalae
Phylum - Arthropoda
Class - Insecta
Order - Coleoptera
Family - Scarabaeidae
Genus - Popillia
Genus & species
Popillia japonica Newman

3. Characteristics of the Phylum
Arthropoda
24.1
Segmented bodies (e.g., head, thorax, abdomen).
Paired appendages (e.g., legs, antennae) are jointed.
Chitinous exoskeletion that must be shed.
Bilateral symmetry.
The nervous system is dorsal (belly) and the circulatory system is open and ventral (back).

5. Arthropod Exoskeletons
Joints are made of stiff and flexible cuticle to allow movement.
The exoskeleton is made of many layers of chitin.
hard material that protects the body
must be shed in order to grow

6. Arthropod Classification
Crustaceans—live in oceans,
freshwater streams, and on land
Chelicerates—specialized dagger-like
mouthparts
Insects—most live on land, have six legs
Myriapods—long bodies and many pairs of legs

7. Crustaceans (Marine Arthropods)
24.2
Crustaceans (Marine Arthropods)
two distinct body sections, cephalothorax and abdomen
one pair of appendages per segment
two pairs of antennae
exoskeleton
carapace

8. Crustacean Appendages
Crustacean appendages are used for a variety of functions.
collecting and manipulating food
attracting females
Protection
claws, antennae, walking legs, swimmerets, and mandibles.

9. Types of Crustaceans. Isopods such as pill bugs have flattened bodies
Decapods such as lobsters and crabs have ten legs.
Isopods such as pill bugs
have flattened bodies
and seven pairs of legs.
Barnacles are sessile filter
feeders wrapped in a hard shell.

10. Chelicerate Arthropod Characters:
Pincher-like mouthparts - chelicerae
NO antennae
Two body regions, usually - cephalothorax & abdomen
Four pairs of legs
Horseshoe crabs and arachnids are only living groups
poison gland
spinnerets
fangs
24.3

11. Arachnids are the largest group of chelicerates.
There are three major groups of chelicerates.
horseshoe crabs
sea spiders
arachnids

12. Arachnids -- Spiders
All spiders make silk and produce venom.

13. CHANGE IN FORM FROM EGG TO ADULT
Metamorphosis
CHANGE IN FORM FROM EGG TO ADULT

14. INCOMPLETE METAMORPHOUS Insects change shape gradually!

15. Complete Metamorphosis Four stages that all look different

16. Insects with Complete Metamorphosis
EGG  LARVA  PUPA  ADULT
beetles
bees, ants, wasps
Flies
butterflies

17. Insects with Incomplete Metamorphosis
EGG  NYMPH  ADULT
fleas
grasshoppers & crickets
Wings NOT fully developed