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The East Mediterranean region is a global biodiversity hotspot for vertebrates and plants. Although oaks ( Quercus) are the dominant tree species in semi-natural Mediterranean forests, the insect species richness associated with East Mediterranean oak forest has been insufficiently studied., Species richness and composition of the saproxylic beetle assemblage, including its seasonal variation, of a stand of old oaks ( Quercus calliprinos) in northern Israel was investigated. Flight-interception traps were used to sample beetles over a period of 2 years. In addition, a set of pitfall traps was placed in the trunk hollows in the second year of the study., Fifty-two saproxylic beetle species were found associated with oaks in the field study. Among them, two saproxylic click-beetle species were previously unknown to science, and eight species represent new records for Israel. Both the number of species and the number of individuals showed two distinct phenological peaks during the year., A preliminary list of saproxylic beetles inhabiting oaks in Israel was prepared and biogeographical distribution, host plants, habitat guild, and activity period are presented for each species. Together with our own data, the literature survey conducted for 19 beetle families established that at least 124 saproxylic beetle species are associated with oaks in Israel while about 40% of them are unique to the Levantine region. As most localities with old-growth oak forest structures are small and isolated, ongoing management should have high priority despite the fact that these forests already receive protection. [ABSTRACT FROM AUTHOR]

Abstract: Forests cover almost 30% of the Mediterranean region today, yet forest management activities have influenced structure and composition of both natural and planted forests. To date no study has been conducted to evaluate the impact of forest management on saproxylic beetle assemblages, although it is known that the Mediterranean is a biodiversity hotspot with a long-lasting human pressure on natural habitats. We provide an overview of saproxylic beetle assemblages of three forest types (mature Pinus halepensis forests, mature Pinus brutia forests, young Quercus calliprinos forests) in the East Mediterranean region using a one-year sample from 12 forest plots located in the north of Israel. The studied forest types differed in forest structure, but we found no significant difference in saproxylic beetle species richness. Aleppo pine forests showed the largest number of saproxylic beetle species. Forests dominated by P. brutia, a non-native tree species in Israel, show the lowest species number of all three forest types. Species composition differs substantially between oak and pine forests. A third of the species found either in P. halepensis or in Q. calliprinos forests being unique to these habitats, while a smaller proportion of unique beetle species is found in P. brutia forests. Several beetle species that were found both in oak and pine plots in our study develop exclusively on broadleaved shrubs or trees. This may be explained by the small distances between the studied pine trees and oaks in their proximity. Biodiversity in pine forests can be increased when these are mixed with broad-leaved trees, e.g. oaks in the understorey layer, as can be observed the natural regrowth in most of the planted pine stands in our research area. There is some evidence from other studies that older successional stages of oak forests are likely to host more species overall than the mature pine forests studied here. In order to enhance structural diversity foresters should allow for aging of single trees or stands, regardless of the tree species. [Copyright &y& Elsevier]