[Edited_by_A._Ciancio,_C.N.R.,_Bari,_Italy_and_K.(Bookos.org)

CITRUS PEST MANAGEMENT IN ITALY
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capitata (Wiedemann) and the Two spotted spider mite Tetranychus urticae (Koch)
(on lemon) (Barbagallo, 2000). Together with these species, some others such as the
Citrus green bug Closterotomus trivialis (Costa), the Cotton or Melon aphid Aphis
gossypii (Glover), the Chaff scale Parlatoria pergandii Comstock, the Olive black
scale Saissetia oleae (Olivier), the Fig wax scale Ceroplastes rusci (L.) and the
Leafroller Archips rosanus (L.), have been showing recrudescent infestations over
the last decades.
2.1. Aonidiella aurantii (Maskell)
The armoured scale A. aurantii (Hemiptera: Diaspididae), commonly known as
California red scale, is native to South-Eastern Asia (Southern China and
Indochinese peninsula) but is spread almost worldwide.
The armour of the mature female is almost round in shape (1.6–2.1 mm), clear
brown almost translucent with the nymphal exuviae located at the centre. Generally
the scale appears reddish in colour because of the red body visible through the
cover. The shield remains tightly attached to the substrate when the scales are
moulting or reproducing. A characteristic, well developed, whitish ventral coating
isolates the body of the female from the plant tissues. Before mating the body of the
female is pear-shaped, pale yellow and its cover assumes a greyish colour; soon after
mating, due to the production of eggs, the cephalothoracic portion of the body
rapidly develops and reaches the apex of the abdomen. The crawlers that
progressively emerge from under the female, move around to find a suitable place to
settle and begin to produce a white cottony circular cover (“white cap” stage).
Starting from the second instar, males begin to develop in a different way forming
an elongated and usually clearer cover. The adult male (1.6–1.7 mm) emerges after
four moults and is yellowish-orange, with some brown sclerified portions on the
dorsal region.
Figure 1. Aonidiella aurantii colonies on Tarocco orange.