Phylum Arthropoda - III
(Subphylum Hexapoda)
Bio 1413: General Zoology
(Ziser,2008)
[Ex. 15, p 223]
Classification:
Subphylum: Hexapoda (insects)
body plan: head, thorax, abdomen
compound eyes
single pair of antennae
mandibles for feeding
three pairs of unbranched legs
two pairs of wings
respiration by tracheae
includes only invertebrates that can fly
Major Groups:
Apterygota (wingless insects; springtails, silverfish)
Pterygota (flying insects; flies, butterflies, etc)
Lab Activities:
Insects (p 225):
1. Grasshopper (preserved):
preserved: grasshoppers
a. External anatomy, know: head, thorax, abdomen,
slide: insect spiracle, wm
compound eye, antennae, ocelli, labrum,
mandibles, wings, walking legs, typanum,
spiracles, cerci, ovipositor
b. Internal anatomy, know: crop, gastric caecae, stomach,
intestine, malpighian tubules, ovaries, testes
2. Honeybee anatomy (use a dissecting scope) (p 227)
a. Honeybee legs
use a dissecting scope to compare to those of the
grasshopper, note:
slide: honeybee legs, wm
Pollen Brushes - stiif haired, on most proximal tarsal segment of
fore and middle legs
Antenna Cleaner - at jct of tarsus and tibia of foreleg
Pollen Comb - rows of stiff hairs in inner surface of first tarsal
segment of hind legs
Pollen Basket - on outer surface of tibia of hind legs
b. Honeybee stinger
slide: Honey Bee Stinger
recognize the stinger as a modified ovipositor; compare to ovipositor
of female grasshopper – How do they differ?
3. Diversity of insect anatomical features. As you look at the slides
below note the variation and diversity of each organ; how the
same part can be modified in a variety of ways to perform
different functions
a. Insect Leg Types
slide: Insect Leg Types, wm
note how the same basic parts are modified in a variety of
ways; the structure of the legs is an important
characteristic for classification
b. Insect Wing Types
slide: Insect Wing Types
note the variation and diversity of wing types in insects;
certain wing types are characteristic of specific insect orders
c. Insect Antennae
slide: antennae types, wm
note the variation in structure of the antennae, some
of these characteristics are important in identifying
orders and species of insects
d. Modifications of Insect Mouthparts
compare the mouthparts of a butterfly with that of
a mosquito and compare to the mouthparts of
the grasshopper
4. Be able to use key (p 240-244) and illustrations to identify
assorted insects to ORDER.
Demonstrations
slides: butterfly proboscis
Culex, wm
Musca domestica,
Preserved insects
Slides: Pediculus (louse)
Aphids, wm
• Examples of Apterygote Insects (insects without wings)
• Examples of Pterygote Insects (insects with wings)
• Insect camoflage and mimmicry
note the examples illustrated
• Insect Metamorphosis
-be able to distinguish between incomplete and complete metamorphosis
-observe the variety of body forms for various immature insects and compare them with their
mature counterpart. which are examples of complete metamorphosis and which are
examples of incomplete metamorphosis
• Grasshopper Anatomy
use these illustrations to help you identify the anatomical features of the grasshopper
Notebook Suggestions
 What are the similarities and differences between the hexapods (insects) and other subphyla of
Arthropods
 What characteristics do ALL insects have, which are modified and how in each of the major orders.
 Compare insect respiratory system, excretory system and sensory structures to those same systems in
the other subphyla of Arthropods.