Any member of several families of sap-sucking insects (order Homoptera) whose bodies are covered by a waxy shell (the scale). The eggs are protected by the female's body or scale or a waxy filamentous mass. Scale insects may attack any part of a plant, but each species is host-specific. Many species are serious plant pests; others have commercial value. The lac insect is used in a red dye and in shellac. Cochineal, a red dyestuff, consists of the dried, pulverized bodies of females of the species Dactylopius coccus. Seealso cottony-cushion scale, San Jose scale.

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or walking leaf

Any of about 25 species of flat green insects (family Phylliidae) with a leaflike appearance. Leaf insects, which range from India to the Fiji Islands, are about 2.3 in. (60 mm) long. The female has large leathery forewings (tegmina) that lie edge to edge on the abdomen and resemble, in their vein pattern, the midrib and veins in a leaf. The hind wings have no function. The male has small tegmina and ample, non-leaflike, functional hind wings. The newly hatched young are reddish, but become green after feeding on leaves.

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Any member of the class Insecta, the largest arthropod class, including nearly 1 million known species (about three-fourths of all animals) and an estimated 5–10 million undescribed species. Insect bodies have three segments: head, thorax (which bears three pairs of legs and usually two pairs of wings), and many-segmented abdomen. Many species undergo complete metamorphosis. There are two subclasses: Apterygota (primitive, wingless forms, including silverfish and bristletails) and Pterygota (more advanced, winged or secondarily wingless forms). The approximately 27 orders of Pterygota are generally classified by wing form: e.g., Coleoptera (beetles), Diptera (dipterans), Heteroptera (bugs). Insects are found in almost all terrestrial and freshwater and some marine habitats.

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Hexapod may refer to:

• Subphylum Hexapoda, a group of arthropods including the insects
• Hexapod (robotics), six-legged walking robots
• Stewart platform, a machine platform supported by six struts, used in robotics