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Scale Insect

Scale Insects are highly specialized insects belonging to order Hemiptera, suborder Homoptera, super-family Coccoidea. Scale insects are diverse in habit and structure. Females are wingless, legless and obscurely segmented, have poorly developed eyes and antennae, and may be protected by a waxy, cottony or hard, scalelike covering. Males are tiny, lack mouth parts, and are short-lived. Crawlers, the first juvenile stage, are mobile and function in dispersal. Most species are 0.5-2.0 mm long, but one measures over 25 mm.

Interaction with Humans

Many cause serious damage to plants. In Canada, major pests include oystershell scale, pine needle scale, and San José scale; they are controlled by predators, parasites, insecticides and fumigants. Cottony maple scale, which occurs throughout the US and Canada, was introduced from Europe.

Some species are beneficial: one produces lac, from which shellac is made; several have been dye sources; one produces Indian wax, used for medicinal purposes; another produces China wax, formerly used for candles.

In some cases, damage caused by insects can leave trees more vulnerable to disease and even introduce pathogens directly, such as in the case of beech bark disease, a disease complex formed between a beech-scale insect and a fungus.

Fly

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Deer Fly

Centipede

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Arthropoda

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Crab

Aphid

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Aphids are small soft-bodied insects that suck plant sap. They are very often green in colour, but may be yellow, pink, red, blue, purple, brown, or black.