animals (and plants) are given scientific names that
individuals hatch from the egg only partially
resembling the adults. The immatures, or nymphs, d o
always consist of two words; the first word is the
genus name (the first letter is always a capital), the
not have wings. (Winged insects are always adults and
second is the species name (always lower case). Both
have finished their growth.) Fourteen orders develop
are written in italics or underlined (e.g., Musca
in this way. Some of these orders have many species
domestica). Well-known species can be given non-
and include many pests. Nymphs and adults are often
scientific names, called "common names" (e.g., house
found together and eat the same food.
Group 3. Complete Metamorphosis
The orders that develop by complete
metamorphosis make a complete change in appearance.
GROWTH AND DEVELOPMENT
These orders contain the majority of insect species. In
fact, they number more than all of the other species
The arthropod body is confined in its exoskeleton.
in the entire animal kingdom! This major group
This outer covering can expand only a little at pliable
consisting of nine orders, includes beetles, moths and
or soft places. It does not grow continuously.
butterflies, flies, fleas, and the stinging insects, ants,
Arthropods grow in stages. They form a new soft
bees and wasps.
exoskeleton under the old one, then shed -- or molt --
Insects with complete metamorphosis hatch from
the old one. The soft new one fits the accumulated
eggs as larvae, (grubs, maggots and caterpillars). The
growth. The new exoskeleton is white at first, but it
mission of the larval stage is to feed and grow. Larvae
hardens and darkens in a few hours. After the molting
continue their development through a number of molts
process, which usually takes place in hiding, the
until they become mature; then, they change into
arthropod resumes its normal activities.
pupae. Not active like larvae; the purpose of the pupal
stage is one of change or body rearrangement resulting
in a complete change into the adult stage. The mission
Arthropods hatch as tiny individuals and grow by
of the adult is to reproduce.
molting, usually keeping the same appearance until
they become adult. [The reader will find that a
Considerations of Pest Management
spectacular and very important exception occurs in the
These developmental stages of insects with
complete metamorphosis support rather than compete
The insect class is divided into groups according
with each other. It is as if the single species is
to the way insects change during their development.
represented by two or three completely different
This change is called by the technical term,
metamorphosis, which means "change in form". Three
animals with different needs and habits: The larvae
feed and live in one spot; they sometimes leave that
main types of metamorphosis have been identified.
spot to pupate a short distance away. The adult
Group 1. Simple Metamorphosis
emerges and often lives in another area, returning to
the larval feeding site only to lay eggs. For this
This group including the order of springtails and
silverfish, makes no drastic change. They simply hatch
reason, pest controllers manage species with complete
and grow larger by molting periodically. Three small
metamorphosis in different ways according to the
orders are included together in this group.
different stages, where each lives, and what they do.
The reader will want to pay special attention to
Group 2. Gradual Metamorphosis
sections that discuss the growth cycle, behavior, and
In this group (e.g., cockroaches, crickets,
harborage (the area in which the animal lives and finds
grasshoppers, boxelder bugs, earwigs, etc.),
its food) of each animal.
Module One, Chapter 1, Pg 2