Download Arthropods - Ball State University

Arthropods
Subphylum Mandibulata
•Class Myriapoda
•= chilopoda and diplopoda
Chilopods
~ 3,000 centipedes
Single pair of antennae
Pair of mandibles
Eyes simple when present
Diplopoda
~ 10,000 millipedes
Mostly deposit feeders in soil
some carnivores
2 pair legs per segment
Hexapoda = six-footed
•Class Insecta
•Well-studied
•Impacts on ag, pollination, disease
vectors, commercial products
•~1,000,000 species described
•4X more to be described
Insect taxonomy
Silverfish = Order Zygentoma
Subclass Pterygota = winged insects
Winged insects
Order Ephemeroptera: mayflies
wings cannot be folded
adults live hours to few days
larvae are aquatic
Winged insects
Order Odonata = damselflies and
dragonflies
wings cannot be folded
aquatic larvae
predators
Winged insects
Order Orthoptera = crickets, grasshoppers
produce noise by rubbing wings
Winged insects
• Order Plecoptera = stoneflies
– Adults live only long enough to mate
– Aquatic larvae, drumming behavior
Winged insects
Order Hemiptera = true bugs
piercing mouthparts
Winged insects
Order Coleoptera = beetles
front pair of wings form
protective cover
Winged insects
• Order Diptera = true flies
– Posterior wings are reduced = halteres
– Aquatic larvae in some
Winged insects
Order Trichoptera = caddisflies
like small moths, feed on liquids
aquatic larvae = case-builders
Winged insects
• Order Lepidoptera = moths and butterflies
– Larvae = caterpillars
Insect body
Head, thorax, abdomen
Insect head
•4 paired appendages:
•One pair antennae
•Mandibles, maxillae,
labium = lower lip
Insect thorax
•Two pairs of wings
•Reduced 2nd pair in diptera = halteres
Insect senses
•Tympanal organs = hearing
•Compound eyes and ocelli
Gas exchange
Water balance
Insects produce uric acid from
protein metabolites
Malpighian tubules
Insect development - instars
Metamorphosis
hemimetabolous = gradual
holometabolous = larva – pupa -adult