Palaeocimbex quadrimaculatus

Palaeocimbex quadrimaculatus (O.F. Müller)

(Sometimes placed in the genus Cimbex).

Taxonomic placing: Insecta, Holometabola, Hymenoptera, Symphyta, Cimbicidae.

Common name: Almond sawfly.

Geographical distribution: Europe and the Near East.

Host plants: Various Rosaceous fruit trees.

Morphology: The adult is 20-25 mm in length, with a brown head, and black thorax. The abdomen is also black and bears two large dark-brown bands. The wings are light brown and the antennae are about 8 mm long, black at their base, becoming yellow-orange at the enlarged tip. The larvae are whitish-grey, with a large head and many yellow and black spots, reaching a length of 40-50 mm. They have 3 pairs of thoracic legs and 7 pairs of prolegs.

Life cycle: This sawfly is univoltine. In spring it lays eggs (about 80/female) on almond leaves, which are eaten by the emerged larvae. At maturity they drop to the soil, construct a cocoon in which they oversummer and overwinter, pupating towards the following spring and then emerging.

Economic importance: Palaeocimbex quadrimaculatus is a pest mainly of almonds, but may also attack apricots, cherry, peaches, pears and plums. Injury to young almond trees can be very significant, the trees becoming completely defoliated, which will reduce next-years’ yield.

Management

Biological control: The ichneumonid endoparasitoids Listrognathus mactator (Thunberg), Opheltes glaucopterus (L.) and Phobetes nigriceps (Gravenhorst) attack the larvae during spring, develop therein during summer and winter, emerging next spring. Several bacteria were isolated from dead P. quadrimaculata that within 10 days caused 100% mortality of the 3rd instar larvae under laboratory conditions.

References

Özgen, H. 2014. Ichneumonid parasitoids of the sawfly Cimbex quadrimaculata (Möller) feeding on almonds in Antalya, along with a new parasitoid and new record. Turkish Journal of Zoology 38: 657-659.

Cakici, F.O., Ozgen, İ., Bolu, H., Erbas, Z., Demirbağ, Z. and Demir İ. 2015. Highly effective bacterial agents against Cimbex quadrimaculatus (Hymenoptera: Cimbicidae): isolation of bacteria and their insecticidal activities. World Journal of Microbiology and Biotechnology 31: 59-67.

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