Phylum Arthropoda/Echinodermata

Brought to you by: Kate Lee, Beth Reinert, Christie Currie, and Maggie Gorski

Main Characteristics Segmented animals Five subphylums: Trilobita, Cehelicerata,

Crustacea, Myriapoda, and Hexapoda Arthropods include insects, spiders, trilobites,

shrimp, lobsters, crabs, etc. Evolved around 545 million years ago around

the same time as chordates evolved

Bilateral symmetry Coeloms Uses exoskeletons for structure and support Exoskeleton has three layers and the tough

covering is called the carapace. Most arthropods shed their exoskeleton

through a process called molting.

Subphylum Crustacea

•Macrocheira kaempferi (Japanese Spider Crab)

Reproduce sexually through internal fertilization

Aquatic crustaceans use swimmerets that transfer sperm to egg.

The eggs then hatch into a free-swimming larva called a nauplius

Through many series of molting, the nauplius eventually develops into the adult form

Reproduction & Development

Food passes through a one way digestive tract (mouth to anus).

Uses a digestive gland to mix food with enzymes

Excess water and wastes are eliminated using green glands.

Digestion and Excretion

Open circulatory system uses hearts and vessels to transport

circulatory fluid throughout the crustacean Uses gills to exchange oxygen and carbon

dioxide for respirationNervous System has clusters of ganglia in the brain that

controls the body (cephalized) Ganglias throughout the body are connected

by a ventral nerve cord

Circulation and Respiration

Tissues include heart tissues, nerve tissues, and gill tissues.

Crustaceans use sensory hairs that sense vibrations and chemicals

Can be terrestrial or aquatic Some crustaceans are up to 4 meters long

Unique Features

The goose barnacle (Lepas anatifera) is an

aquatic crustacean.

SubphylumInsecta

Classes & Examples Order Hemiptera (“half wing”);

true bugs Order Homoptera (“like wing”);

aphids, mealy bugs, cicadas Order Isoptera (“equal wing”);

termites Order Odonata (“toothed”);

dragonflies, damselflies Order Orthoptera (“straight

wing”); grasshoppers, crickets, katydids

Order Coleoptera (“sheathed wing”); weevils, ladybugs, beetles

Order Coleoptera (“sheathed wing”); weevils, ladybugs, beetles

Order Diptera (“two wing”); mosquitoes, flies, gnats

Order Hymenoptera (“membrane wing”); bees, wasps, and ants

Order Lepidoptera (“scaled wing”); butterflies, moths

Bilateral Symmetry

Symmetry

The body of an insect is divided into three tagmata: the head, thorax, and abdomen.

Body Cavity

Tissues Brain, Crop, Aorta,

Gastric Ceca, Ovary, Heart, Tracheae, Anus, Oviduct, Seminal Receptacle, Hindgut, Malphigian tubules, midgut, Ganglion, Ventral Nerve cord, gizzard, salivary glands, and the esophagus.

Characteristics of most insects: a body consisting of a head, thorax, and abdomen; a pair of unbranched antennae; three pairs of jointed legs; and two pairs of wings.

Structure & Support

Digestion & Excretion One way digestive tract Malphigian tubules

which collect water and cellular wastes from the hemolymph and produce a very concentrated mixture of wastes that is deposited in the hindgut and leaves the body with the feces.

Open circulatory system Insects exchanges oxygen and carbon dioxide

with the environment through a complex network of air tubes called trachea.

Circulation & Respiration

Reproduction & Development

All insects have separate sexes and reproduce through internal fertilization

Develop either through incomplete metamorphosis

Or incomplete metamorphosis

Consists of a brain and a ventral nerve cord with ganglia located in each body segment.

Antennae contain sensory structures that respond to touch and smell.

Three simple eyes function to sense the intensity of light Two bulging compound eyes provide a wide field of view

and can detect movement and form images. The tympanum detects sounds Sensory hairs detect touch or movement by vibration

Nervous System

Insect defense: warning coloration, Müllerian mimicry, Batesian mimicry, venomous stingers, spraying noxious chemicals

Unique Characteristics

Insects communicate through pheromone, sound, and light.

The Round Dance The Waggle DanceBee Dances