Family Aleyrodidae

Bodenheimer (Animal Life in Palestine, 1935) has this to say:
White-flies (Aleurodidae) are rare. The yellow Trialeurodes vaporarium on tobacco etc., and the black Aleurodes olivinus on olive-leaves may be mentioned.

From Wikipedia:
The whiteflies, comprising only the family Aleyrodidae, are small hemipterans. More than 1550 species have been described. Whiteflies typically feed on the underside of plant leaves. While feeding damage can cause economic losses, it is the ability of whiteflies to transmit or spread viruses that has had the widest impact on global food production. In the tropics and subtropics, whiteflies (Hemiptera: Aleyrodidae) have become one of the most serious crop protection problems. Economic losses are estimated in the hundreds of millions of dollars. While several species of whitefly cause crop losses through direct feeding, a species complex, or group of whiteflies in the genus Bemisia are important in the transmission of plant diseases. Bemisia tabaci and B. argentifolii, transmit African cassava mosaic, bean golden mosaic, bean dwarf mosaic, bean calico mosaic, tomato yellow leaf-curl, tomato mottle, and other Begomoviruses, in the Family: Geminiviridae.
Whitefly damage by feeding: Whiteflies feed by tapping into the phloem of plants, which carries food down the plant to the roots. Plants have vascular tissues that carry water Xylem up the plant, where it combines with photosynthesis to produce the needed food for plant growth. The plants lose turgor and may react to the whiteflies' toxic saliva. As whiteflies congregate in large numbers, they overwhelm plants quickly. It can get so bad that when you tap a leaf, a swarm of whiteflies will go airborne before re-settling under the leaf. They also excrete honeydew, which promotes mold growth and can ruin a cotton crop with its stickiness. They have an unusually modified form of metamorphosis, in that the immature stages begin life as mobile individuals, but soon attach to the plant, and the stage before the adult is called a pupa (though it is not at all the same as the true pupal stage in holometabolous insects).

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