1,000,000 + species “jointed foot” – in reference to their jointed appendages Eumatazoan, triploblastic coelomates Bilaterally symmetrical protostomes Major features of Arthropods: 1.Evolved segmentation 2.Exoskeleton 3.Jointed appendages Open circulatory system The most biologically successful of all animals Well developed senses Prolific reproductively

Over half of all known species belong to the arthropod phulym Diverse organisms Specialized structures (wings) Well adapted senses (compound eyes & antennae) Live in a great variety of environments (exoskeleton – not bound to water) aquatic & terrestrial High reproductive potential (quickly reproduce) Many lay 1,000’s of eggs during life Immeasurably vast ecological impact Food sources Detrivores – eat dead, decaying organisms (nature’s recyclers) Pollinators Help plant populations Pests Fleas, ticks, mosquitoes Agricultural pests “Home invaders”

Exoskeleton – a hardened cuticle of protein and chitin For protection, body structure, and muscle attachment Prevents water loss Thick and hard in some areas Paper thin and flexible in others (jointed areas) Ecdysis – molting process Allows arthropods to grow Molting is energetically expensive and leaves arthropods vulnerable Evolved segmentation Fusion of segments and specialization via function of body Tagmata – head, thorax (chest), abdomen Efficient body plan (division of labor)

Modified, specialized, and adapted for: Locomotion (walking legs, “tails”, wings) Wings are actually extensions of cuticle Feeding (mouthparts, pincers) Sensory reception (antennae) Defense (pincers, stingers) Copulation (egg and sperm deposit)

Digestion system is complete (annelid like) Respiratory Internalized lungs or gills for diffusion of gas, despite having an exoskeleton Most insects have a tracheal system that is branched leading to pores along the exoskeleton (believed that this system limits the size of bugs) Open circulatory system Hemolymph is the fluid pumped by the heart through short arteries and spills into sinus spaces, called hemocoels, surrounding tissues and organs (not part of the body cavity) Reproductive Extremely prolific Males seek females Mostly egg layers

Nervous system consists of nerve ring surrounding pharynx and connected to nerve cords (annelid-like) Sensory system is highly developed and Complex Compound eyes (most insects) 1,000’s of lenses – vision looks like a tile mosaic Excellent at detecting motion Antennae (touch/vibrations and smell sensors) Pheromones - Chemical messages or “smells” Used by insects of a species to communicate with members of the same species. Reproduction (mate attraction) Trail markers (ants) Alarm signals (ants, bees) Queen – messages to colony

Subphylum Chelicerata Class Merostomata (horseshoe crabs) Class Arachnida (spiders, scorpions, ticks, mites) Subphylum Crustacea Class Malacostraca (lobsters, crabs, shrimp) Class Maxillopoda (barnacles & copepods)) Subphylum Hexapoda Class Insecta (beetles, butterflies, ants, etc.) Subphylum Myriapoda Class Chilopoda (centipedes) Class Diplopoda (millipedes)

Class Merostomata (horseshoe crab) Primitive arthropod – fossils over 450 million years old 4 species Hard, plate-like exoskeleton Long tail used to flip themselves over Reproduce by spawning in huge numbers on the beach Eggs become food for many species Copper based blue blood (important for the medical industry)important for the medical industry)

Class Arachnida (spiders, scorpions, ticks, mites) Six pair of appendages 1 st set – near the mouth, modified for feeding and or defense Mouth parts Fangs/jaws 2 nd set – on the head, modified for feeding, moving, sensing, or reproduction Feelers, pincers, copulatory limbs 3 rd -6 th set - 4 pair of walking legs (8 legs) Each leg has grasping tips and 7 segments No antenna, no wings Body composed of 2 tagma: Cephalothorax – fused head and thorax Abdomen Many eyes Egg layers, some species carry young around on back (brooding) Predominately terrestrial - Breathe with book lungs (membranes look like pages)

Predators of mainy other arthropods (bugs) – larger spiders will prey on small vertebrates (fish, frogs, mice, birds)larger spiders Fangs Spinnerets Webs Multiple sets of eyes Sensory hairs covering body Females are larger than males Males are often eaten by females after mating

Predators – mainly of other arthropods (bugs)other arthropods Grasping pincers Stinging tail (with varying degrees of venom toxicity depending on diet, size, and other environmental factors) Burrowers – need soil to survive Extremely durable Live in desert climates, Himalayan mountains, Brazilian rainforests, and in NC Can survive on very little food Have the ability to slow metabolic rate Florescent under UV light Florescent

Mites are very small Feed on organic material Ticks are large blood sucking mites Feed on blood, fall off of host, molt, and wait for new host.

Insects Mostly terrestrial and many can fly (wings vary) Escape predators, find food and mates, great for species dispersal 3 pairs of walking legs (6 total legs) Body divided into 3 distinct regions Head, thorax, abdomen Mouthpart specialization Chewing, lapping, piercing, sucking Antennae, present and highly developed Reproduction: Advertising via bright colors, sound, pheromones Sexual reproduction allows females to store sperm and produce many batches of eggs Metamorphosis during development: Incomplete – egg to nymph (mini). Nymph goes through a series of molts eventually becoming sexually mature adult Complete – egg to larva (feeding and growing stage – maggot, grub, caterpillar). Larva to pupa (adult development). Adult emerges from pupa. Many insects only mate once in a life time Extremely important ecological roles: Food source, Recyclers, Pollinators, Biodiversity Pests who compete with humans for food and space…

26-”ish” Orders: Blattodea (cockroaches) Coleoptera (beetles) Dermaptera (earwigs) Diptera (flies & mosquitoes) Hemiptera (“true bugs”) Hymenoptera (ants, bees, wasps) Isoptera (termites) Lepidoptera (butterflies & moths) Odonata (dragonflies & damselflies) Orthoptera (grasshoppers, crickets, katydids) Mantodea (mantises) Phasmida (stick insects) Phthiraptera (lice) Siphonaptera (fleas) Thysanura (silverfish) Trichoptera (caddisfly)

Chilopoda (centipedes) Diplopoda (milipedes)

Class Maxillopoda (barnacles & copepods) Barnacle examples …

Class Malacostraca (lobsters, crabs, shrimp)