Species composition and population dynamics of dominant dendrophagous moths (Lepidoptera) in St. Petersburg and its environs
The paper summarizes new and literature data on the species composition, trophic relationships and population dynamics of phyllophagous lepidopterans dominant on woody plants in St. Petersburg and its environs (Russia). Larvae of these species mostly live hiddenly (e. g., leaf miners and leaf rollers); some of them are invasive. The data were accumulated during approximately a hundred years of observations and field collections. Hiddenly living species is a dominant group within the complex of studied phyllophagous lepidopterans in St. Petersburg and Leningrad Province (27 species from 13 families). A change in the composition of dominant species of pests of dogrose, cherry, elm, poplar, and other woody plants has been recorded. Outbreaks were recorded during the XX century in some species, for example, Phyllonorycter salicicolella (Gracillariidae), Archips rosanus (Tortricidae), Leucoma salicis, Lymantria monacha, and Orgyia antiqua (Erebidae), but since about 1980, the population density of these species remains at a very low level. Another group of species, which includes Phyllonorycter populifoliella (Gracillariidae), Batrachedra praeangusta (Batrachedridae), Acleris bergmanniana and Epinotia abbreviana (Tortricidae), demonstrated a sharp increase in their population density in 1990-2000s, a phenomenon which had not been observed before. The possible causes of such population dynamics are discussed. The dominant species of phylophagous microlepidopterans, including a few recent invaders (e. g., Cameraria ohridella and Phyllonorycter issikii, Gracillariidae) and adventive species (e. g., Ph. populifoliella and Ph. acerifoliella, Gracillariidae) pose a serious threat to woody plants in St. Petersburg and Leningrad Province.