ECOS Guide to the Ecology of the Northern Rockies
 
   
 

Glossary of Insect Terms

Abdomen
Body region behind thorax, usually has 10 segments, can have appendages at the tip.
Ametabolous metamorphosis
A type of simple metamorphosis where the immature insects look like small versions of the adults.
Antenna
Plural=antennae. In insects, a pair of appendages used as sensory organs; located on the head above the mouthparts.
Apterous
Without wings.
Bioindicator
An animal whose presence or absence indicates the biological condition of a habitat.
Cerci
Pair of structures at the tip of the abdomen.
Chewing mouthparts
Type of mouthparts that allow an insect to chew, bite or grind its food.
Chrysalis
Pupal stage of butterflies.
Cocoon
A covering spun or constructed by a larva as protection for the pupa.
Complete metamorphosis
The type of insect development where wings develop internally and there is a pupal stage.
Crepuscular
Active at dusk or dawn.
Crochets
Hooks at the end of prolegs in Lepidoptera.
Detritivore
An animal who eats dead and decomposing animal or plant material.
Dun
Subimago; the first winged stage of a mayfly, not reproductively mature.
Elytra
Singular = elytron. A modified, thickened and hardened front wing of an insect; usually only referred to in the order of beetles.
Gall
Abnormal proliferation of plant tissue stimulated by insect or pathogen attack; typically a globose or spindle-shaped swelling on a stem, branch or root.
Gill
Respiratory organ.
Grub
The larva of a beetle.
Haltere
Modified hind wing in flies (Diptera).
Hemimetabolous metamorphosis
A type of simple metamorphosis where the immature insects are aquatic and the adults are terrestrial.
Honeydew
Sugary, liquid excrement produced by certain aphids, scales, and other insects that feed on plants.
Instar
The period or stage between molts during larval development; first instar is the stage between the egg and the first molt.
Labium
Lower lip of insect mouth.
Larva
Plural = larvae. Usually considered the immature stage (between egg and pupa) of an insect that goes through complete metamorphosis.
Maggot
The larva of a fly.
Mandible
Mouthpart; insects have two which occur on each side of the mouth.
Naiad
The immature stage of insects that go through hemimetabolous metamorphosis.
Nymph
The immature stage of an insect that goes through simple metamorphosis.
Ovipositor
Structure used by females to lay eggs.
Parasite
An organism that lives at the expense of another; usually by invading it and causing disease.
Parthenogenetic
Reproduction from unfertilized eggs.
Paurometabolous metamorphosis
A type of simple metamorphosis where the nymphs and adults live in the same habitat, eat the same food and generally look alike except the adults have wings.
Piercing mouthparts
Sometimes referred to as a beak; allows the insect to pierce tissue and consume fluid such as nectar, plant juices or blood.
Proboscis
Type of mouthpart that allows the insect to suck up fluids.
Proleg
Fleshy, abdominal legs of some larvae.
Pronotum
Top portion of the prothorax.
Prothorax
One of the three thoracic segments, closest to the head.
Pupa
Plural = pupae. The stage of an insect between larvae and adult for those that go through complete metamorphosis.
Sclerotize
Hardened.
Setae
Bristle or hair.
Simple metamorphosis
Immature insects that go through this type of metamorphosis are usually similar to adults but they do not have full wings and are not reproductively mature.
Social insects
Group of insects who has members that are nonreproductive (sometimes sterile); who cooperate to rear the young; and there is an overlap of generations.
Sponging mouthparts
Some flies have this type of mouthpart; allows the insect to lap up liquids by means of capillary action.
Stridulate
Making a noise by rubbing two structures or surfaces together.
Subimago
The first winged stage of a mayfly, not reproductively mature.
Sucking mouthparts
Type of mouthpart that allows an insect to suck up fluids.
Thorax
The body region behind the head which bears wings and legs; divided into three segments: prothorax, mesothorax and metathorax.
Wing pad
Developing wings on immature insects that go through simple metamorphosis.
 
The ECOS program is sponsored by the University of Montana's Division of Biological Sciences, and the College of Forestry and Conservation. Carol Brewer Program Director, Division of Biological Sciences. Paul Alaback Program Co-Director, College of Forestry and Conservation.
NSF LogoECOS is supported by the GK-12 Program of the National Science Foundation.
Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the National Science Foundation.