Cottony-Cushion Scale

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Cottony-Cushion Scale


(Icerya purchasi), an insect of the family of giant coccids of the suborder Coccidae of the order Homoptera, a dangerous pest of citrus crops. The reddish brown body, which measures 5– mm long, is oval or nearly round. In mature females there is a large (sometimes 25 mm long), white, fluted ovisac. The cottony-cushion scale is native to Australia. As a result of the exportation of seedlings, the insect appeared in all countries in which citruses are cultivated. In the USSR it is found in the Abkhazian ASSR, the Adzhar ASSR, and Krasnodar Krai. The insect harms citrus crops, silver acacia, fig, pomegranate, cypress, and several other plants. There are two or three parthenogenetic generations each year. The larvae winter, and adult females appear in early May. The females soon deposit more than 2, 000 eggs in the ovisac. The larvae hatch in the ovisac and emerge within a few hours. Cottony-cushion scales sometimes congregate in large colonies on shoots, branches, trunks, leaves, and fruits. They suck out the juices of the plant. As a result, plant growth is inhibited and fruit yield is decreased.

The most widely applied control measure is the use of the predatory Australian lady beetle (Rodolia cardinalis), an example of a biological control measure for plant protection. When there is a large population of cottony-cushion scale, insecticides are used (a chemical control measure).


Borkhsenius, N. S. Chervetsy i shchitovki SSSR. Moscow-Leningrad, 1950.
Rubtsov, I. A. Vrediteli tsitrusovykh i ikh estestvennye vragi. Moscow-Leningrad, 1954.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Bioecological and population studies of the cottony-cushion scale, Icerya purchasi Mask., and its natural enemies, Rodolia cardinaIis Mul.
This inadvertent introduction had catastrophic effects, as did many later accidental introductions, including that of the cottony-cushion scale insect (Icerya purchasi, order Homoptera, originally from Australia), which reached the United States in 1890.
citri (Diaspididae); Icerya purchasi Maskell (Monophlebidae), P.
Segun Cock (1985), esta especie no identificada fue introducida en 1961 desde Trinidad a Barbados contra Icerya purchasi Maskell (Homoptera:Margarodidae), con resultados desconocidos.