Thrips

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"Thunderbug" redirects here. For the NHL mascot, see List of National Hockey League mascots.

iThrips

Scientific classification

Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Subclass:	Pterygota
Superorder:	Exopterygota
Order:	Thysanoptera Haliday, 1836

Families

Suborder Terebrantia
   Merothripidae
   Uzelothripidae
   Aeolothripidae
   Adeheterothripidae
   Heterothripidae
   Thripidae
   Fauriellidae
Suborder Tubulifera
   Phlaeothripidae

Image:Ponticulothrips diospyrosi.jpg A thrips (plural thrips) (Thysanoptera) is a tiny, slender insect with fringed wings (thus the scientific name, from the Greek thysanos (fringe) + pteron (wing)). Other common names for thrips include Thunderflies, Thunderbugs and Corn Lice. Thrips species feed on a large variety of sources both plant and animal by puncturing them and sucking up the contents. A large number of thrips species are considered pests, because they feed on plants with commercial value. Some species of thrips feed on other insects or mites and are considered beneficial, while some feed on fungal spores or pollen. So far around 5000 species have been described.

Thrips are generally tiny (1 mm long or less) and are not good flyers — though they can be carried long distances by the wind. In the right conditions many species can explode in population and swarm everywhere, making them an irritation to humans.

Like the word sheep, the word thrips is used in both the singular and plural numbers. So while there may be many thrips there can also be a solitary thrips. The word thrips is from Greek, meaning Wood Louse.<ref>Kirk, W. D. J. (1996). Thrips. Naturalists’ Handbooks 25. The Richmond Publishing Co. Ltd.</ref>

Thrips feed by piercing plant cells with their paired maxillary stylets, which form a feeding tube. Thrips, unlike the Hemiptera, have only one mandibular stylet, or if a second is present it is greatly reduced and non functional. The one fully formed mandibular stylet is used to pierce an entry hole in plant cells or pollen grains, wherein the maxillary stylets can easily enter the cell and suck out the contents. Thrips feed on hundreds of different crop plants, especially during flowering where they also feed on pollen.

Many thrips are pests of commercial crops due to the damage caused by feeding on developing flowers or vegetables which causes discoloration, deformities, and reduced marketability of the crop.

Thrips in the genera Frankliniella (flower thrips) and Thrips also spread plant diseases through the transmission of viruses, such as Tospoviruses. The western flower thrips, Frankliniella occidentalis, has a worldwide distribution and is considered the primary vector of plant diseases caused by Tospoviruses. Over 20 plant infecting viruses are known to be transmitted by thrips. These enveloped viruses are considered among some of the most damaging of emerging plant pathogens around the world. Virus members include the tomato spotted wilt virus and the Impatiens necrotic spot viruses.

To suvive the winter temperatures most thrips species over-winter as either adults or as pupae under ground litter. A typical flower thrips generation time will be from 7 to 22 days depending on the temperature. The eggs are about 0.2 mm long and reniform (kidney shaped), and may take on average 3 days to hatch. Thrips have 2 larval stages then go through a prepupal and a pupae stage, with the adults taking 1 to 4 days to reach sexual maturity. In the two suborders, the females of the Suborder Terebrantia are equipped with an ovipositor which they use to cut slits into plant tissue into which they insert their eggs, one per slit, while females of the Suborder Tubulifera lack an ovipositor and lay their eggs singly or in small groups on the outside surface of plants.

Image:Thysanoptera-thripidae-sp.gif

Thrips are commonly known to invade modern LCD monitors and LCD televisions.[1]

[edit] References

Scientific Papers on thrips feeding and gustatory sensillae.

Nault, LR. 1997. Arthropod transmission of plant viruses: A new synthesis. Annals of Entomological Society of America. Vol. 90: 521-541.

Hunter, WB, Ullman, DE, & A. Moore. 1994. Electronic Monitoring: Characterizing the feeding behavior of western flower thrips (Thysanoptera: Thripidae), pp. 73-85. In History, Development, and Application of AC Electronic Insect Feeding Monitors. Ellsbury, MM, Backus, EA, & DL. Ullman (editors), Thomas Say Publications in Entomology.

Hunter, WB, & DE. Ullman. 1992. Anatomy and ultrastructure of the piercing-sucking mouthparts and paraglossal sensilla of Frankliniella occidentalis (Pergande)(Thysanoptera: Thripidae). International Journal of Insect Morphology & Embryology. Vol. 21: 17-35. Pergamon Press, Elsevier Science Ltd., Great Britain.

Hunter, WB, & DE. Ullman. 1989. Analysis of mouthpart movements during feeding of Frankliniella occidentalis (Pergande) and F. schultzei Trybom (Thysanoptera: Thripidae). International Journal of Insect Morphology & Embryology. Vol. 18: 161-171. Pergamon Press, Elsevier Science Ltd., Great Britain.