Epidiaspis leperii

Epidiaspis leperii (Signoret)

Taxonomic placing: Insecta, Hemimetabola, Hemiptera, Sternorrhyncha, Coccomorpha, Coccoidea, Diaspididae.

Common name: Italian pear scale.

Geographical distribution: Europe to Turkey, North and South America, Africa.

Morphology: The body of the female is pear-shaped, initially pink, later dark red, unsclerotized. The dorsal macroducts are two-barred, slender, 3-4 on each side of the pygidium, none on the pre-pygidial segments. The pygidium bears one pair of central, large lobes with notched outer margins, and 3-4 pairs of increasingly smaller pairs, becoming spur-like. Large, comma-shaped paraphyses arise from the lobes on either side of the pygidium. The anus is located about two-thirds of the distance between the median lobes and the vulva, around which are placed 5 groups of perivulvar pores, 2 on either side and one above the vulva. Each group with about 10 pores. Shield about 1.6 mm in diameter, circular, thin, light grey and slightly convex, the darker juvenile exuviae are placed slightly off center. The males are dark yellow, about 1 mm in length, with oval, grey shields and the 1st instar exuvium is placed near one end.

Host plants: Many Rosaceae, especially pears, also Juglans regia L. and olives.

Life history: Epidiaspis leperii is monovoltine, passing the winter as immature females in diapause. Development resumes in April-May, with prolonged oviposition (lasting 1-2 months) of about 50 eggs/female. The yellowish crawlers often settle under moss and lichens on old trees. Development continues during summer and the mated females enter diapause in autumn.

Economic importance: Heavy infestations that accumulate on branches and twigs cause bark cracking, depressions, distortion, breakage or death, and result in reduced tree vigor. Pears (which react by producing gummy secretions), apples and plums are especially affected and their fruit production is reduced. In Turkey the pest damages cherry trees. It may also affect olives and various ornamentals.

Management.

Chemical control: Small pest numbers do not harm trees. Heavy infestations are hard to control with chemicals (such as oils) during winter, because the scales are concealed under the abundant moss and lichen coverings. These growths can be removed with copper and lime sulfur sprays, and appropriate sprays can then be applied. Insect growth regulators did not shorten the adult diapause but inhibited egg hatching.

Biological control: Epidiaspis leperii is attacked by several aphelinid parasitoids, such as Aphytis mytilaspidis (Le Baron), but their combined effect is insufficient.

References

Abd El-Kareim, A.I., Darvas, B. and Kozár, F. 1989. Effects of some juvenoids on prediapausing and postdiapausing females of Epidiaspis leperii (Hom., Diaspididae). Acta Phytopatalogica et Entomologica Hungarica 24: 473-482.

Bianchi, H. and Bénassy, C. 1979. La cochenille rouge du poirier, Epidiaspis leperii Sign. (Homoptera, Coccoidea) ravageur en France du prunier. Annales de Zoologie - Ecologie Animal 11: 493-511.

Bodenheimer, F.S. 1953 The Coccoidea of Turkey. II. Revue de la Faculté des Sciences de l’Université d’Istanbul 18: 1-61.

Geier, P. 1949 Contribution à l’étude de la cochenille rouge du poirer (Epidiaspis leperii Sign.) en Suisse. Revue de Pathologie Végétale et d’Entomologie Agricole de France 28: 177-266.

Geoffrion, R. 1976 La cochenille rouge du poirier. Arboriculture Fruitière 265: 23-31.

Miller, D.R. Davidson, J.A. 1990. A list of the armored scale insect pests. IN: Rosen, D. (editor). Armored Scale Insects, Their Biology, Natural Enemies and Control, Vol. 1, pp. 299-306. Elsevier Amsterdam, the Netherlands, 688 pp.

Websites

https://www.google.co.il/search?q=Epidiaspis+leperii++images&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiZzdmpqdDbAhVIDsAKHZUZD7EQsAQIJA&biw=1280&bih=620&dpr=1.5