C. L. Koch, 1836
Tetranychus urticae (common names include red spider mite and two-spotted spider mite) is a species of plant-feeding mite generally considered to be a pest. It is the most widely known member of the family Tetranychidae or spider mites. Its genome was fully sequenced in 2011, and was the first genome sequence from any chelicerate.
T. urticae is extremely small, barely visible with the naked eye as reddish or greenish spots on leaves and stems; the adult females measure about 0.4 mm long. The red spider mite, which can be seen in greenhouses and tropical and temperate zones, spins a fine web on and under leaves.
This spider mite is extremely polyphagous; it can feed on hundreds of plants, including most vegetables and food crops – such as peppers, tomatoes, potatoes, beans, maize, and strawberries, and ornamental plants such as roses. It is the most prevalent pest of Withania somnifera in India. It lays its eggs on the leaves, and it poses a threat to host plants by sucking cell contents from the leaves cell by cell, leaving tiny pale spots or scars where the green epidermal cells have been destroyed. Although the individual lesions are very small, attack by hundreds or thousands of spider mites can cause thousands of lesions, thus can significantly reduce the photosynthetic capability of plants.
Other than certain aphids, T. urticae is the only animal known to be able to synthesise carotenoids. As in aphids, the genes for carotene synthesis appear to have been acquired through horizontal gene transfer from a fungus.
The egg of T. urticae is translucent and pearl-like. It hatches into a larva, and two nymph stages follow: a protonymph, and then a deutonymph, which may display quiescent stages. The adults are typically pale green for most of the year, but later generations are red; mated females survive the winter in diapause.
Inbreeding is detrimental for fitness in T. urticae. Inbred progeny mature more slowly than outbred progeny, and inbred female progeny have lower reproductive output. T. urticae females apparently can recognize kin and have the ability to avoid inbreeding through mate choice.
|NCBI genome ID|
|Ploidy||haploid (males) / diploid (females)|
|Genome size||90.82 Mb|
|Year of completion||2011|
- D. A. Raworth, D. R. Gillespie, M. Roy & H. M. A. Thistlewood (2002). "Tetranychus urticae Koch, twospotted spider mite (Acari: Tetranychidae)". In Peter G. Mason; John Theodore Huber. Biological Control Programmes in Canada, 1981–2000. CAB International. pp. 259–265. ISBN 978-0-85199-527-4.
- Thomas R. Fasulo & H. A. Denmark (December 2009). "Twospotted spider mite". Featured Creatures. University of Florida / Institute of Food and Agricultural Sciences. Retrieved May 20, 2011.
- Ashutosh Sharma & Pratap Kumar Pati (2012). "First record of the carmine spider mite, Tetranychus urticae, infesting Withania somnifera in India" (PDF). Journal of Insect Science. 12 (50): 50. doi:10.1673/031.012.5001.
- Boran Altincicek, Jennifer L. Kovacs & Nicole M. Gerardo (2011). "Horizontally transferred fungal carotenoid genes in the two-spotted spider mite Tetranychus urticae". Biology Letters. 8 (2): 253–257. doi:10.1098/rsbl.2011.0704. PMC 3297373. PMID 21920958.
- Cytological studies of the two-spotted spider mite Tetranychus urticae Koch (Tetranychidae, trombidiformes). I: Meiosis in eggs. C. C. M. Feiertag-Koppen, Genetica, 1976, Volume 46, Issue 4, pages 445-456, doi:10.1007/BF00128090
- Tien NS, Massourakis G, Sabelis MW, Egas M (2011). "Mate choice promotes inbreeding avoidance in the two-spotted spider mite". Exp. Appl. Acarol. 54 (2): 119–24. doi:10.1007/s10493-011-9431-y. PMC 3084432. PMID 21400191.
- Miodrag Grbić, Thomas Van Leeuwen, Richard M. Clark, Stephane Rombauts, Pierre Rouzé, Vojislava Grbić, Edward J. Osborne, Wannes Dermauw, Phuong Cao Thi Ngoc, Félix Ortego, Pedro Hernández-Crespo, Isabel Diaz, Manuel Martinez, Maria Navajas, Élio Sucena, Sara Magalhães, Lisa Nagy, Ryan M. Pace, Sergej Djuranović, Guy Smagghe, Masatoshi Iga, Olivier Christiaens, Jan A. Veenstra, John Ewer, Rodrigo Mancilla Villalobos, Jeffrey L. Hutter, Stephen D. Hudson, Marisela Velez, Soojin V. Yi, Jia Zeng, Andre Pires-daSilva, Fernando Roch, Marc Cazaux, Marie Navarro, Vladimir Zhurov, Gustavo Acevedo, Anica Bjelica, Jeffrey A. Fawcett, Eric Bonnet, Cindy Martens, Guy Baele, Lothar Wissler, Aminael Sanchez-Rodriguez, Luc Tirry, Catherine Blais, Kristof Demeestere, Stefan R. Henz, T. Ryan Gregory, Johannes Mathieu, Lou Verdon, Laurent Farinelli, Jeremy Schmutz, Erika Lindquist, René Feyereisen & Yves Van de Peer (2011). "The genome of Tetranychus urticae reveals herbivorous pest adaptations". Nature. 479 (7374): 487–492. doi:10.1038/nature10640. PMC 4856440. PMID 22113690.