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

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

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).

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

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

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

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.

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.

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

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

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

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

INCOMPLETE METAMORPHOUS Insects change shape gradually!

Complete Metamorphosis Four stages that all look different

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

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