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Saissetia oleae Olivier
//CLA

Insecta, Homoptera, Lecanidae .

Black scale

Description, Biology, Life Cycle, Damage, Common Names, Images


[R]Description
- Adult: The adult female attaches itself to the host, remaining immobile; scale sub-ovate, convex, measuring 2 to 5 mm x 1 to 4 mm long and 2.0 to 2.5 mm wide. Colour light brown when young becoming darker with age, being dark brown to black at the end of its life-cycle. Typical dorsal H pattern (*) .
- Egg: Sub-ovate; length circa 0.3 mm; white to orange-rose (*) .
- Nymphs: Similar to the adults going through three intermediate instars between egg and adult (*) (*) .

[R]Biology
- Host plants: olive; Citrus; fig; oleander (Nerium oleander) (*) ; ivy (Hedera); apricot; Pittosporum sp. This insect is polyphagous.
- Adults: Adult females about to begin egg laying, appear in April-May. They are preceded by the hibernating 2nd- and 3rd-instar nymphs. Each female lays between 150 to 2,500 eggs.
- Eggs: Oviposition may extend for 10 to 15 days in the spring and twice as long in the autumn. Eggs remain under the female scale. Eclosion occurs after an incubation period of 15-20 days.
- Nymphs: 1st-generation nymphs may appear from June onwards, frequently until the first days of August. Populations composed mainly of nymphal stages and a few young females can be detected simultaneously during September. Some of these young females may lay eggs during this period provided the weather stays mild. The newly emerged nymphs which then appear by the end of October constitute a partial 2nd generation.

[R]Life Cycle
- Newly emerged nymphs move around searching on the host plant for a place to settle down. S. oleae is usually univoltine, although an incomplete generation may occur when the weather stays mild in the autumn. S. oleae hibernates as nymph (in several intars) which begin to feed in the following spring.

[R]Damage
- The feeding process of scale insects includes piercing of the host tissues and sucking the sap. S. oleae occurs on the twigs and leaves usually on the undersides (*) .
The damage is the result of the absortion of nutritional material and water contained in the sap. Sooty mould affects photosynthesis.
Host plants under water stress, however, reduce the S. oleaea degree of attack.


[R]Common Names
DE: Olivenschildlaus ES: Cochonilla negra, Aceiton del olivo FR: Cochenille noire de l'olivier IT: Cocciniglia mezzo grano di pepe PT: Cochonilha da oliveira, Cochonilha negra, Lapa da laranjeira GB: Olive black scale

[R] Images

  1. Saissetia oleae (Bernard) (Coutin R. / OPIE)
    Nymphs Underside of leaf of oleander.
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  2. Saissetia oleae (Bernard) (Coutin R. / OPIE)
    Adult females on olive
  3. Saissetia oleae (Bernard) (Coutin R. / OPIE)
    Parasitized individuals Lateral exit holes of parasites. The plant organs are entirely covered by sooty moulds.
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  4. Saissetia oleae (Bernard) (BASF)
    Pullulation on olive
  5. Saissetia oleae (Bernard) (Daumal J. / INRA Antibes)
    Young females on twig of
    Myrtus
  6. Saissetia oleae (Bernard) (Daumal J. / INRA Antibes)
    Ventral side of females and their eggs Scales have been turned upside down.
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  7. Saissetia oleae (Bernard) (Bénassy C. / INRA Antibes)
    Female and 3rd-stage nymph On oleander.
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  8. Saissetia oleae (Bernard) Female scale insects on an olive twig (Bernard J.-F. / INRA Maroc)

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