Whiteflies
| Whitefly | |
|---|---|
 |
|
| Whiteflies (Trialeurodes vaporariorum) | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Hemiptera |
| Suborder: | Sternorrhyncha |
| Superfamily: | Aleyrodoidea |
| Family: | Aleyrodidae |
| Subfamilies | |
| Synonyms | |
|
Aleurodidae |
|
Aleurodicinae
Aleyrodinae
Udamoselinae
Aleurodidae
Whiteflies are small Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described.
The Aleyrodidae are a family in the suborder Sternorrhyncha and at present comprise the entire superfamily Aleyrodoidea, related to the superfamily Psylloidea. The family often occurs in older literature as "Aleurodidae", but that is a junior synonym and accordingly incorrect in terms of the international standards for zoological nomenclature.
Aleyrodidae are small insects, most species with a wingspan of less than 3 mm and a body length of 1 mm to 2mm. Many are so small that their size complicates their control in greenhouses because they can only be excluded by screening with very fine mesh; in fact they can enter mesh so fine that many of their natural enemies cannot come in after them, so that unchecked whitefly populations in greenhouses rapidly become overwhelming. Some "giant whitefly" species exist, some of which may exceed 5 mm in size. This sometimes is associated with sexual dimorphism in which one sex is markedly larger than the other. Such dimorphism is common in the Sternorrhyncha, in which the males of most scale insects for example are tiny compared to the female. Remarkably however, in some giant tropical species the males are much larger than the females.
Like most of the mobile Sternorrhyncha, adult Aleyrodidae have well-developed antennae, which in most species in this family are seven-segmented. As in many Hemiptera, there are two ocelli, which generally in the Aleyrodidae are placed at the anterior margins of the compound eyes. The compound eyes themselves however, are rather remarkable; there are many examples in entomology in which the upper and lower regions of the compound eye differ both functionally and anatomically, and in some families that are adapted to living on water surfaces, such as the Gyrinidae, they even may be divided into upper and lower eyes for vision in air and under water. However, although it is not clear why Aleyrodidae should need any such adaptation, many have a distinct constriction between the upper and lower halves of the compound eyes in both sexes. In some species there is a complete separation. The degree of separation is useful in recognising the species; for instance, one way to tell adult Bemisia from Trialeurodes is that the upper and lower parts of the compound eyes are connected by a single ommatidium in Bemisia, while in Trialeurodes they are completely separate.
...
Wikipedia