The first record of two non-native ambrosia beetles in Slovenia: Ambrosiodmus rubricollis (Eichhoff, 1875) and Ambrosiophilus atratus (Eichhoff, 1875) (Coleoptera: Curculionidae, Scolytinae).

In September 2017, during the monitoring of the non-native ambrosia beetle Xylosandrus germanus (Blandford, 1894), one specimen of an unknown ambrosia bark beetle species was collected in Slovenia. The specimen was trapped in an ethanol-baited trap located in Klavze (46° 09´ 39˝ N, 13° 48´ 7˝ E), in the western part of Slovenia. The most characteristic feature distinguishing the specimen from other known ambrosia beetle species occurring in Slovenia was the asperities that covered the entire surface of the pronotum. Based on the scientific literature concerning the non-native bark and ambrosia beetles in Europe (Kirkendall Faccoli 2010) and illustrated identification keys (Rabaglia et al. 2006; Faccoli et al. 2009), we identified the beetle by its morphological characteristics as Ambrosiodmus rubricollis (Eichhoff, 1875). As a result of this find, a specific monitoring was set up in 2018 in Slovenia with the aim to improve the knowledge about occurrence and distribution of A. rubricollis in this country.

Essential-Oil Variability in Natural Populations of Pinus mugo Turra from the Julian Alps.

The composition and variability of the terpenes and their derivatives isolated from the needles of a representative pool of 114 adult trees originating from four natural populations of dwarf mountain pine (Pinus mugo Turra) from the Julian Alps were investigated by GC-FID and GC/MS analyses. In total, 54 of the 57 detected essential-oil components were identified. Among the different compound classes present in the essential oils, the chief constituents belonged to the monoterpenes, comprising an average content of 79.67% of the total oil composition (74.80% of monoterpene hydrocarbons and 4.87% of oxygenated monoterpenes). Sesquiterpenes were present in smaller amounts (average content of 19.02%), out of which 16.39% were sesquiterpene hydrocarbons and 2.62% oxygenated sesquiterpenes. The most abundant components in the needle essential oils were the monoterpenes δ-car-3-ene, ß-phellandrene, α-pinene, ß-myrcene, and ß-pinene and the sesquiterpene ß-caryophyllene. From the total data set of 57 detected compounds, 40 were selected for principal-component analysis (PCA), discriminant analysis (DA), and cluster analysis (CA). The overlap tendency of the four populations suggested by PCA, was as well observed by DA. CA also demonstrated similarity among the populations, which was the highest between Populations I and II.