Lepidosaphes malicola Borchsenius
Common name: Armenian comma hard scale, Kirgis comma scale.
Taxonomic placing: Insecta, Hemimetabola, Hemiptera, Sternorrhyncha, Coccomorpha, Coccoidea, Diaspididae.
Morphology: Female shield purple-brown, elongated or twisted, dependent on the colony’s density, up to 3.5 mm in length, with the darker juvenile dorsal exuviae at the narrow end. Body pale-yellow, with lateral sclerotic protuberances (“bosses”) on some abdominal segments. The two-barred dorsal macroducts are arranged in transverse rows, six pairs on the pygidium’s margin being larger. The perivulvar pores are arranged in five clusters, about 25-50 in two groups on either side of the anus. The fifth group, of about 15-20 pores, is situated just below the anus. The shield of the winged male (if present) is slightly paler. The crawlers are white.
Geographical distribution: Turkey, Southern Asia, Morocco, Yugoslavia, and Greece.
Host plants: Many Rosaceae, also Salix and Juglans (walnuts).
Life history: This pest occurs mainly on the trunks and branches of host trees, sometimes also on the leaves and fruit. A female may lay about 100 eggs, overwinters in the egg stage and the insect is bivoltine, its crawlers appearing in early summer and in autumn.
Economic importance: Lepidosaphes malicola is an important, damaging pest of apples and other fruit trees, like plums. Very heavy infestations on trunk and branches can cause tree twig die-back and even death. The sucking spots of the scales on apples become red, resulting in disfiguring spotting. It is also a pest of roses.
Management
Sampling: Four branches/tree are selected in early spring and the number of scales counted per surface area unit.
Chemical control: Organophosphates applied in the spring, as the crawlers emerge, provided good control, as did white oils.
Biological control: Several aphelinid ectoparasitoids, including Aphytis mytilaspidis, A. libanicus Traboulsi and Coccobius testaceus (Masi) attack the pest, as does the parasitic mite Hemisarcoptes malus (Shimer) (Hemisarcoptidae). Predators include the coccinellid Chilocorus bipustulatus. Their overall effect on reducing pest numbers and damage is not clear.
References
Babayan, G.A. and Oganesyyan, S.B. 1979. Natural enemies of the Armenian mussel scale (Lepidosaphes malicola Borchs.) and possibilities of conserving them in the presence of chemical treatments. Biologicheskii Zhurnal Armenii 32: 194-199 (in Russian).
Esmaili, M. 1967. Apple oystersheil scale Lepidosaphes malicola Borkh (Hom. Diaspidoidae) and its control. Bulletin of the University of Tehran College of Agriculture 1967: 23+8.
Jalivand, K., Shirazi, M., Ali, V.H. and Samih, M.H. 2013. A Preliminary Study on Natural Enemies of Coccoidea (Hemiptera, Sternorrhyncha) in Kermanshah Province, Western Iran. Acta Phytopathologica et Entomologica Hungarica 48: 299–308.
Japoshvilli, G. and Karaca, I. 2002. Coccid (Homoptera: Coccoidea) species of Isparta Province, and their parasitoids from Turkey and Georgia. Turkish Journal of Zoology 26: 371-376
Mostaan, M., Seyedoleslami, H., Farivar Mahin, G., Farahbakhch, G. and Daftari, K., 1972: Complementary study of the biology and methods of control of Lepidosaphes malicola Borkh. in Iran. Entomologie et Phytopathologie Appliquees 33: 4-20 (in Iranian with a French summary).
Uygun, N., Sengonca, C., Erkiliç, L. and M. Schade, 1998. The Coccoidea fauna and their host plants in cultivated and non-cultivated areas in the East Mediterranean region of Turkey. Acta Phytopathologica et Entomologica Hungarica 33: 183-191.
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