Bark and Ambrosia Beetles (Coleoptera, Curculionidae: Scolytinae) of Northwest Russia: History of the Study, Composition and Genesis of the Fauna

An essay of the fauna of bark beetles (Coleoptera: Curculionidae: Scolytinae) in five federal subjects of Northwest Russia is presented. The species composition of scolytids in Leningrad, Novgorod, Pskov, and Murmansk provinces as well as the Republic of Karelia is analyzed in comparison with the bark beetle faunas of adjacent Estonia and Finland. The history of investigation of the bark beetle fauna in Northwest Russia starting from the XVIII century and up to date is discussed, and modern knowledge on the regional bark beetle fauna is considered. The distribution of “northern” and “southern” bark beetle species in the region is discussed, and a southward increase in species richness is demonstrated. The genesis of the bark beetle faunas of individual provinces is analyzed with respect to the host plant distribution in the postglacial period (Holocene). It is shown that the border between the middle and the southern taiga subzones running across Leningrad Province is also the northern distribution boundary of numerous bark beetle species. Special attention is paid to expansion of several bark beetle species into Northwest Russia in the last decades caused by different factors; the northward range expansion of the small spruce bark beetle Ips amitinus (Eichhoff, 1872) and elm bark beetles from the genus Scolytus Geoffroy, 1762 is considered in more detail. The absence of monitoring of the elm bark beetle populations has led to uncontrolled reproduction of the pests, spread of Dutch elm disease, and significant economic losses. Rare bark beetle species deserving inclusion in the regional Red Data Lists are named. Attention is drawn to the insufficient knowledge of the bark beetle fauna in nature reserves and other protected areas in Northwest Russia. The damage caused by the most economically important bark beetles, namely the European spruce bark beetle Ips typographus (Linnaeus, 1758) and pine shoot beetles of the genus Tomicus Latreille, 1802, in the boreal forest zone is briefly reviewed. Some taxonomic problems which remain to be solved in order to refine the local bark beetle species lists in Northwest Russia are outlined. The contribution of researchers from St. Petersburg Forest Institute to the knowledge of bark beetle biology in the region and in the whole of Russia is specially considered.