Tomicus destruens is a Mediterranean pine shoot beetle (Scolytinae) known as a phloem-feeding, secondary, and primary pest of pine trees (Pinus spp.). In Slovenia, three species of the genus Tomicus have been recorded: T. minor, T. piniperda, and T. destruens, which was recently documented in coastal areas. It is generally widespread in the Mediterranean region and is better adapted to warmer climate conditions. Morphologically, it closely resembles T. piniperda, which has often led to misidentifications in the literature. It occurs on Mediterranean pine species and attacks black pine (P. nigra), which is commonly found in southwestern Slovenia. The aim of the research was to determine the distribution and investigate the overlap in ranges of T. destruens and of the other two mentioned species of the genus Tomicus and assess their occurrence dynamics. For this purpose, 16 cross-vane traps were placed in the broader Karst Forest management region in stands of black pine, divided into three different temperature zones (cold, moderate, warm). T. destruens was documented only at locations where the mean temperature of the coldest quarter was ⡥ 4 °C. This was in the warm zone and at the southernmost location of the moderate zone (Kastelec), while T. piniperda was recorded in the moderate and cold zones. T. minor was documented at all locations and zones, and in the highest numbers. We also found that the peak capture of T. destruens occurred in late autumn (October), while the peak capture of T. piniperda and T. minor occurred in spring (April). The Kastelec location stood out, as T. destruens was observed during the spring (February and April) rather than in the autumn season. At all locations where we recorded T. destruens, we also documented the presence of T. minor. However, we did not document any locations where T. destruens and T. piniperda were present simultaneously, nor did we find locations where all three species were present simultaneously.
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