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Whiteflies

I hesc insects resemble tiny moths. The head of these bugs carries a pair of seven-segmented antennae, and the conspicuous wings are either white or mottled, with a distinctive dusting of white, powdery wax over the surface.

• UI I . CYCU; The females lay their eggs on tiny stalks on the undersides of leaves. When the nymphs first hatch out, they move around. However, they lose their legs at the first molt, and after this they become sedentary sap-suckers.

• OCCIIRRKNCK Worldwide, especially in warmer regions. On a range of host plants.

• KKMARK Many whiteflies are serious pests. Well-known examples include Trialeurodes vaporariorum (see picture) and Bemista tabact, which is a widespread pest of cotton and other important crops.

Common aphids

I hesc aphids are small, soft-bodied, and mostly green, pink, black, or brown. The abdomen usually carries a pair of short tubes, called cornicles, from which a substance is secreted to deter predators.

• I .III CYCU: I cmalcs produce large colonics by parthenogenesis (asexual reproduction in which eggs develop without fertilization) and usually give birth to nymphs. Winged adults migrate to a host plant where sap-feeding and parthenogcnetic reproduction continues. Later, more winged aphids fly back to the original host plant, where the males and females mate and lay eggs once more.

• OCCI RRKNCK Worldwide. Wherever host plants arc found.

• RKMARK With their huge reproductive potential, aphids are the most destructive of all plant-eating insects. Virtually all crop species are affected by their feeding and by the viral diseases that thev transmit.

antennae, with four to six segments wingless adult female young being born cornicles

MACROSIPIII M AUilPRONS, the American Lupin Aphid, is now also found throughout many parts of Kurope. This species is a pest and carries diseases such as yellow mosaic virus.

adult, with pale underside white, powdery wax iRIAUl ROMS VAPORARIORUM, the Greenhouse Whitefly, is a widespread pest of cucumbers and tomatoes grown under glass. It may also attack field crops in warm conditions.

Superfamily COCCOIDKA

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