Uniramian Superclasses

Superclass Hexapoda: The Insects. As previously mentioned, insects are the most successful of all animal phyla. They differ from crustaceans by having a single pair of antennae (rather than two) and legs based on a uniramus plan (with unbranched appendages). The exoskeleton, though similar in structure to that of crustaceans, lacks significant calcium deposits. Characteristics that separate them from the other arthropods include three pairs of legs and (usually) two pairs of wings. Examine the preserved and living insects on display to appreciate the variability in their body plans and adaptations. Pictures of major orders are here for study.

Superclass Myriapoda. Myriapods include the centipedes and millipedes (the term "Myriapoda" means "many footed"). Like the insects, they are primarily terrestrial in habits, have a single pair of antennae, uniramus appendages, and mouthparts based on mandibles. Unlike the insects, the myriapod body is divided into only two segments, a head and trunk (instead of an insect's three segments- the head, thorax, and abdomen) and the eyes are not as complex. The trunk segments may range from a few to more than a hundred.

• Class Chilopoda- the Centipedes. Centipedes have one pair of legs per body segment and poison glands (most, however, are not dangerous to humans). They prefer moist places and feed on earthworms and insects. Examine the centipedes on demonstration so that you can recognize their general structure.
• Class Diplopoda- the Millipedes. Millipedes have two pairs of legs per body segment and do not possess poison glands. Like centipedes, they prefer moist habitats, but they are either herbivorous or scavengers.

Dissection Figures

Bee legs

Grasshopper dissection

Roach dissection 1

Roach dissection 2

Grasshopper mouth parts

Insect Integument	Insect Mouthparts	Insect Mouthparts	Insect Mouthparts
Insect Mouthparts	Insect Mouthparts	Insect Mouthparts	Insect Mouthparts
Insect Mouthparts	Insect Wings	Insect Wings	Insect Wings
Insect Wings	Insect Wings- Halteres	Insect Legs	Insect Legs
Insect Legs	Insect Legs	Insect Legs
			Chilopoda and Myriapoda