Main menu | General information | Species menu | Natural control | Identification key | Field activities | Image gallery |Bibliography



The posterior section of the three sections (head-thorax-abdomen) of an insect's body. The abdomen contains the reproductive and excretory organs, and the bulk of the digestive system. The abdomen bears no functional legs in the adult stage.

Antenna (pl. antennae)
The paired sensory organs, borne one on each side of the head.

Occurring on the anterior portion of a body segment where the angle of the surface turns from a horizontal to a vertical position.

Occurring on the anterior margin of a body segment.

Aphid (Aphididae)
A family of insects related to whiteflies and planthoppers. Aphids are soft-bodied, sometimes called plant lice, and feed by sucking juices of plants. See Honeydew.


Bacterium (pl. bacteria)
Minute living organisms which are neither animals nor plants. Bacteria is a plural word, the singular is bacterium. Newspaper reporters commonly, but wrongly, use the plural (bacteria) as if it were singular. There are large numbers of species. Some bacteria are entomopathogens.

Many families of 4-winged insects (including hundreds of species worldwide) in which only the second pair of wings is used for flying. The first pair is toughened and shortened and used only as covers for the second pair. When beetles are not flying, the second pair of wings is folded under the first pair of wings.


Campaniform sensillae
A sensory receptor visible externally as an area of thin cuticle, domed and usually oval in shape.

Contact pesticide
A compound that causes death or injury to insects when it contacts them. It does not have to be ingested. Often used in reference to a spray applied directly to the pest.



An organism (generally a bacterium, virus, protozoan, or fungus) causing disease in insects.


Part of the system of biological classification: a group of closely-related genera. All thrips possessing a tubular-shaped, terminal abominal segment belong to the family Phlaeothripidae. The name of a family of animals (e.g., Phlaeothripidae) always has a capital initial letter and always ends in -idae. The family name is not placed in italics and is not underlined.

The pesticide product as purchased, containing a mixture of one or more active ingredients, carriers (inert ingredients) and other additives making it easy to store, dilute, and apply.

Fungus (pl. fungi)
Living organisms which are neither animals nor plants, the singular is fungus. There are large numbers of species. Mushrooms and molds are fungi. Some fungi are entomopathogens.


Generalist natural enemy
A natural enemy with a broad range of diet. Cattle egrets, for example, eat many kinds of insects, and are not specialized natural enemies of any of them. Generalist enemies are not used nowadays in classical biological control though some such uses did occur, especially in the 19th century, before biological control became a profession. Generalist natural enemies may, however, be purchased commercially and released to provide biological control of some pests.

Genus (pl. genera)
Part of the system of biological classification: a group of closely related species. The word is singular (a genus), and its plural is genera (two genera). The genus name is usually place in italics or underlined, and it has a capital initial letter.

Legless insect larvae.


A mixture of sugars and other plant-derived chemicals excreted by some species of aphids and by some species of insects in families related to aphids. When these insects feed on plants, honeydew drips from them onto plant leaves or onto the ground. Fresh honeydew may be fed upon by other insects as an energy source. Ants of many species are avid feeders on honeydew, and they may even guard the aphids against predators and parasitoids to protect this energy source. Unconsumed honeydew on plant leaves promotes the growth of a black fungus called sooty mold, which may become so dense that it interferes with the metabolism of the plant. Contrast with nectar.
An organism (animal or plant) fed upon by a parasite or parasitoid. When insects or nematodes feed upon plants they are considered parasites of those plants, and the plants are referred to as host plants.


Small animals with three pairs of jointed legs and one pair of antennae, at least in the adult phase. Mole crickets, tachinid flies, and sphecid wasps all have this arrangement in the adult phase. However, some insect larvae (grubs) are legless. Spiders and ticks have four pairs of jointed legs, centipedes and millipedes have many more pairs, and these are not insects.

A pesticide used specifically to manage or prevent damage cause by insects. Sometimes generalized to be synonymous with pesticides.

The period or stage between molts, numbered to designate the various periods; e.g. the first instar is the stage between the egg and first molt.

One of the setae occurring in a row between the compound eyes.




Larva (pl. larvae)
One of the phases in the life cycle of some insects, such as wasps and flies. A young insect which hatches from the egg in an early stage of development and differs fundamentally from the adult; e.g., a maggot is the larval form of a fly. Many insect larvae are very different n appearance from the adults. Insect larvae do not have wings. Insect larvae feed, and grow, and molt several times.

Several very different insects can be leafminers: flies, beetles, or moths. In all cases it is the immature that bores through the leaf usually leaving a noticeable trail. One beetle is a very serious pest of black locust, while one mote is a serious pest of citrus.
Life cycle
There are two basic kinds of life cycles in insects. Some (for example mole crickets) have three phases: egg-nymph-adult. Others (for example sphecid wasps and tachinid flies) have four phases: egg-larva-pupa-adult. (Thrips life cycle diagram)


The first pair of jaws in insects, stout and tooth-like in chewing, needle- or sword-shaped in piercing-sucking insects, the upper lateral jaws of a biting insect.

the process in which an immature insect casts its skin in order to grow. A new skin (which develops under the old skin) is a larger size.


Natural enemy
A predator, parasite, parasitoid or pathogen.

Many families of long, legless, worm-shaped animals, including tens of thousands of species worldwide. Some species are aquatic, in freshwater or the sea. Some species are parasites of birds, mammals, or other vertebrate animals. Some species are parasitoids of insects. Others feed on plant roots.

One of the phases in the life cycle of some insects, such as thrips. Insect nymphs look quite similar to the adults, but are small and lack wings. Insect nymphs feed, and grow, and molt several times.


Ocellus (pl. ocelli)
One of two (or one of three) very small, simple eyes on the top of the head of some adult insects.

One of the primary divisions of the classification system. Consists of several to many families.

Egg-laying. To oviposit means to lay eggs. This is an activity of all adult female insects.


An organism that lives in or on the body of its host without killing the host, but usually debilitating the host to some extent. Dog fleas are examples of parasites; note how they feed as parasites of dogs during their adult phase, while in the larval stages they are not parasitic (and are not on dogs). Lice, on the other hand, are parasites from the time they hatch from eggs throughout their lives. See parasitoid

An organism that, during its development, lives in or on the body of a single host individual, eventually killing that individual. Larra wasps, Ormia flies, and Steinernema nematdoes are examples of parasitoids; note that the wasps and flies feed during their larval stages, while in the adult stages they feed on the nectar of plants. Many people use the word parasite when they really mean parasitoid; this is unfortunate because it obscures the lethal effect of parasitoids.

A disease-causing organism.

A stalk or stem supporting an organ or other structure for example, the second segment of the insect antenna.

A substance or agent used to kill pests. Comes in many different formulations and types. There are residual, and non-residual (contact) pesticides. Pesticides are also described as insecticides, herbicides, fungicides, nematicides, and rodenticides depending upon the class of pests they are being used to control.

An organism that, during its development, consumes more than one prey individual. Tiger beetle larvae are examples of predators; note that their adults, too, feed as predators.

The first segment of the thorax, it bears the anterior or first pair of legs but no wings.

Protozoan (pl. protozoa)
Minute animals whose entire body consists only of a single cell. Protozoa is a plural word, the singular is protozoan. There are large numbers of species. Some protozoa are entomopathogens.
One of the setae occurring in a row along the posterior margin of the compound eye.

Occurring on the posterior portion of the body segment where the angle of the surface turns from a horizontal to a vertical position.

Occurring on the posterior of the body segment.

Pupa (pl. pupae)
One of the phases in the life cycle of some insects, such as moths, flies, beetles, wasps, and bees. It is the intermediate stage between the larva and the adult. Insect pupae do not feed.

These are synthetic compound produced to duplicate or improve more or less successfully on the biological activity of the active principles of the pyrethrum plant. Pyrethrum is a natural botanical insecticide the active principles of which are extracted from the flowers of the pyrethrum plant, and are known collectively as "pyrethrins".



Refers to property of a substance (pesticides are one example) that allows it to remain in an area for an extended period.


A ring of subdivision of the body or of an appendage between areas of flexibility associated with muscle attachments.

Seta (See-Ta) (pl. setae (See-Tay))
A hardened, hairlike projection surrounded at the base by a small ring.

The basic unit of classification in biology. Examples are the bald eagle, the polar bear, the monarch butterfly, and the tawny mole cricket. The word is both singular (a species) and plural (two species). Species are grouped into genera, and genera are grouped into family. The words kind, sort, type, strain, and variety are not part of this classification even though newspaper reporters often use them as if they were.

Spider mite
These arthropods are not insects, but are in the same order as ticks. They are very small and require strong hand lens to see. Most are plant feeders and can do considerable damage. Some are important predators of other spider mites.

Any definite period in the development of an insect; e.g. egg stage, larval stage, etc.

A word used to label some pathogens (including insect pathogens) according to their geographical origin. For example, in the last few years a Hong Kong strain and a Beijing strain of human influenza have been labelled. Strains of the insect pathogen Beauveria bassiana likewise have been labeled. Strain does not mean the same things as species.


The middle section of the three sections (head-thorax-abdomen) of an insect's body. The thorax is packed with muscles for the wings and legs which arise from that section. The thorax itself consists of three parts named in order: prothorax, mesothorax, and metathorax.



Simple organisms which are neither animals nor plants, consisting of a nucleic acid (either DNA or RNA) and a protein coat (singular virus). Some viruses are entomopathogens.
The intermediate host, of disease-producing organisms, which conveys them.


These are very small insects, seldom more than 2 or 3 mm in length, that resemble tiny moths. The adults of both sexes are winged and are usually covered with a white dust or waxy powder. First instars are active and called crawlers. Later instars are sissile and look like scales. They have piercing-sucking mouthparts which they use to suck sap from the leaves of plants. They also excrete large mounts of honeydew which sooty-mold grows upon. Some whitefly species are serious pests of cultivated plants. See Honeydew.