Agriculture Reference
In-Depth Information
—the head, thorax, and abdomen.
Figure 3.1
shows the adult ant and its body
regions.
1.
Head
The head contains antennae, eyes, and mouthparts. The antennae vary in
size and shape and can be a help in identifying some pest insects. Insects have
compound eyes, made up of many individual eyes. These compound eyes en-
able insects to discern motion, but probably not clear images.
The four general types of mouthparts are:
•
chewing
•
piercing-sucking
•
sponging
•
siphoning.
Chewing mouthparts
contain
toothed jaws that bite and tear the food.
Cockroaches, ants, beetles, caterpillars, and grasshoppers are in this group.
Piercing-sucking mouthparts
consist of a long slender tube which is forced
into plant or animal tissue to suck out fluids or blood. Insects with these
mouthparts are stable flies, sucking lice, bed bugs, mosquitoes, true bugs, and
aphids.
Sponging mouthparts
have a tubular tonguelike structure with a
spongy tip to suck up liquids or soluble food. This type of mouthpart is
found in the flesh flies, blow flies, and house flies.
Siphoning mouthparts
are formed into a long tube for sucking nectar. Butterflies and moths have
this type.
2.
Thorax
The thorax contains the three pairs of legs and (if present) the wings. The
various sizes, shapes, and textures of wings and the pattern of the veins can be
used to identify insect species.
The forewings take many forms. In beetles, they are hard and shell-like;
in the grasshoppers, they are leathery. The forewings of flies are membranous;
those of true bugs are part membranous and part hardened. Most insects have
membranous hindwings. The wings of moths and butterflies are membranous
but are covered with scales.
