Locust - of damp sandy soil to lay the eggs The eggs hatch...

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Locust life cycle The desert locust ( Schistocerca gregaria ) is a species of grasshopper. It develops by incomplete metamorphosis, i.e. there is no larval stage. The eggs hatch into wingless nymphs which resemble miniature, incomplete adults. In order to grow, the nymph needs to shed its hard outer skin ( cuticle ) and expand its body before the new cuticle hardens. Each stage between moults is called an instar . At each moult, the nymph develops more adult features until, after the 5 th moult it is a fully formed adult with wings. For the first five instars, the nymphs are called ‘hoppers’ and move by crawling or hopping along the ground. They feed on the natural vegetation by cutting off pieces with their jaws. When they develop wings, they fly to a new area where they feed, mate and reproduce. The female extends her abdomen to about 5 cm below the surface
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Unformatted text preview: of damp sandy soil to lay the eggs. The eggs hatch in 10-20 days, depending on the temperature 1 st instar nymph (8mm) 3 rd instar nymph (20mm) 5 th instar nymph (50mm) wing bud developing wings Parts of the world subject to locust invasion Adult (80mm) jaws fore-wing abdomen Locusts differ from other grasshoppers in their tendency to form swarms. While they are scattered, the hoppers and adults do little damage, eating the natural vegetation. When the density of hoppers reaches a critical level, they band together and move as a group of sometimes many thousands. When they take to the wing, they form swarms as large as several square kilometres. The swarms can travel for over a thousand kilometres and when a swarm lands on a food crop, it can destroy the crop completely. © D.G. Mackean...
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