Chaetoptelius vestitus (Mulsant and Rey)
(Also known as Hylesinus vestitus Mulsant and Rey, and as Acrantus vestitus (Muls. & Rey))
Systematic position: Insecta, Holometabola, Coleoptera, Curculionidae. (Formerly placed in the family Scolytidae, now Scolytinae).
Common name: Pistachio beetle, pistachio bark beetle.
Host plants: Pistachio (Pistacia vera L.), other species of Pistacia and olives.
Geographic distribution: Mediterranean countries, Iran and Crimea.
Morphology: The adult body is dark-brown, about 2.5-3.5 mm in length. The dorsum of the thorax is densely punctated. The dark elytra are longitudinally punctated, bear many stiff hairs and have large pale areas. The larva is apodous, mostly white with a brown head.
Life history: The adults of this univoltine, xylophagous beetle emerge in April-May. They fly to young twigs of healthy trees and bore short, feeding tunnels into the terminal or floral buds, thereby destroying them. During summer and winter the beetles hibernate within the pistachio twigs. At the end of winter the beetles fly to dying or pruned branches wherein they excavate reproductive galleries and lay their (approximately) 80-85 eggs/female.
Economic importance: The tunnels dug in young P. vera twigs weakens them, may facilitate their breakage, induce up to 30% bud loss, curtail further growth and cause fruit drop and yield reductions.
Horticultural methods: Improving tree health by suitable irrigation, pruning, fertilization and weeding. Leaving a few dying trees or cut branches over winter, in order to attract ovipositing adults and then burning these trap trees.
Biological control: A braconid and a pteromalid parasitoids attack this beetle, as do several predatory beetles and mites; their overall controlling effects has been estimated to be around 10% of the pest population.
Chebouti-Meziou, N., Doumandji, S.E., Chebouti, Y. and Bissaad, F.Z. 2009. A study on the biology and incidence of Chaetoptelius vestitus (Mulsant & Rey) infesting Pistacia vera L. in the central highlands of Algeria. Arab Journal of Plant Protection 27: 123-126.
Fariwar-Mehin, H. 2002. The important beetle pests of the pistachio trees in Iran. Acta Horticulturae 591: 549-552.
Fragkoyan, A.P. 2006. Biological cycle of Chaetoptelius vestitus (Mulsant & Rey, 1860) (Coleoptera, Scolytidae) in Thessaloniki (Greece). Ph.D. thesis, Aristotle University of Thessaloniki. Pp. 313 (in Greek, with an English Abstract).
Lababidi, M.S. 1998. Biological and ecological studies on the pistachio bark beetle Hylesinus vestitus M. & R. (Coleoptera: Scolytidae) under field condition in Syria. Arab Journal of Plant Protection 16: 74-80.
Schneider, F. 1958. Some insect pests of pistachio in Syria. Plant Protection Bulletin, F.A.O. 6: 65-71.