Arge scita (Symphyta: Argidae): a potential emerging phytophagous for almond?

Abstract

Infestations of Arge scita (Mocsáry, 1880) were recorded for the first time in Italy in summer 2022. Almond trees showing severe leaf damages, caused by the sawfly larvae feeding on the leaf lamina were recorded in the Salento peninsula of the Apulia region (southern Italy). Severely infested trees had a defoliated looking-appearance, with the lamina of the whole foliage completely consumed, with only the thick middle vein and petioles remaining attached to the trees. The occurrence of A. scita on the infested trees was confirmed by molecular and morphological characterization of specimens of larvae at different stages and adults. The simultaneous presence on the infested trees of eggs, larvae of different ages, cocoons and adults suggests that most likely this sawfly in our environmental conditions behave as a multivoltine species. Further investigations and surveys are needed to assess the live cycle and the host range, as well as to understand whether this phytophagous could represent a serious threat in areas where almond trees are cultivated.