Eutetranychus palmatus Attiah

Taxonomic placing: Acari, Prostigmata, Tetranychoidea, Tetranychidae.

Common name: None.

Geographical distribution: This mite occurs in Egypt and in the south of Israel.

Host plants: Eutetranychus palmatus has been found on various Palmae, including the date palm, (Phoenix dactylifera L.), Washingtonia and Hyphaene.

Morphology: The adult female is about 0.4-0.5 mm in length, red-brown, with an oval body and legs that are about as long as the body. The male is reddish, smaller, its hysteronotum is pointed and the legs are longer than the body. The dorsal setae are short and serate, not placed on small tubercles. The rounded eggs are pale-brown.

Economic importance: Eutetranychus palmatus is a minor pest of date palm fruit (apparently more of the cultivar ‘Barhi’), whose feeding produces exudates that later become covered by dust as well as by the mites’ shed skins. Its damage may be masked by that of Oligonychus afrasiaticus Attiah (with which it often co-occurs), and could become more severe in the absence of O. afrasiaticus.

Life history: Little is known about the biology of Eutetranychus palmatus. It develops thorough the year on the fronds, moving onto fruit during mid-summer, earlier than O. afrasiaticus, and back to the fronds when the dates turn yellow. Like other Tetranychoidea, this mite is arrhenotokous.

Management:

CHemical control: The use of acaricides is recommended only in very heavy infestations; otherwise it is not necessary to control this mite.

References

Attiah, H.H. 1967. The genus Eutetranychus in U.A.R. with descriptions of three new species (Acarina: Tetranychidae). Bulletin de la Societe Entomologique d’Egypte 51: 11-16.

Gerson, U., Venezian, A. and Blumberg, D. 1983. Phytophagous mites on date palms in Israel. Fruits 38: 133-135.

Palevsky, E., Lotan, A. and Gerson, U. 2010. Evaluation of Eutetranychus palmatus (Acari: Tetranychidae) as a pest of date palms in Israel. Israel Journal of Plant Sciences 58: 43-51.