Phyllonorycter apparella, a new record and a new pest of trembling aspen (Populus tremula) in Turkey

Phyllonorycter apparella (Herrich-Schaffer, 1855) (Lepidoptera: Gracillariidae) is a new record for the Turkish fauna and a new trembling aspen (Populus tremula L.) pest for Turkey. Its biology, damage and infestation ratio were studied in Sankamis (Kars), Turkey, during 1996 and 1997. P. apparella has one generation a year. The developmental stages of the pest are described briefly. P. apparella hibernates in the adult stage. At the beginning of June, the adults appear. Females deposit their eggs on both leaf surfaces, generally one by one, 7-10 days after emerging. The early instars (sap-feeding larvae) start to mine mostly from the underside of leaves. Each mine has one larva, and each leaf may have up to 26 mines. The last instar (tissue-feeding larva) begins to pupate in the mine after mid August. The adults emerge from mid September to the beginning of October, and move to the trunks of old pine trees, where they hibernate in bark crevices. The infestation level may be as high as 90% of the leaves on some trees.