THE PHYLOGENETIC-RELATIONSHIPS OF 7 EUROPEAN IPS (SCOLYTIDAE, IPINAE)SPECIES

In Central Europe seven Ips species are characterized by differences i n morphology, structure of galleries, host specificity and aggressiven ess, These species were analysed by allozyme markers and by sequencing 567 bp of the mitochondrial cytochrome oxidase I gene, in order to de fine their phylogenetic relationships, Orthotomicus erosus and Tomicus minor were taken as outgroup species. The data revealed high inter-sp ecific and low intra-specific sequence divergence, Plotting the observ ed sequence divergence caused by transversions (Tv) and transitions (T s) and the level of saturation for Ts and Tv of each codon position sh owed that the third positions were highly saturated by multiple substi tutions, Maximum parsimony analysis produced two groups: (1) I, typogr aphus, I. cembrae, I, amitinus, I, duplicatus and I, acuminatus, (2) I . mannsfeldi, I, sexdentatus and the two outgroups, In all analyses th e species of the first cluster were put together and I, typographus an d I, cembrae, and I, mannsfeldi and O, erosus emerged as sister pairs, The data do not support a common ancestor for the seven European Ips species, The eight-spined bark beetles (except I, mannsfeldi) and I. a cuminatus formed a monophyletic group, The close relationship of I, ma nnsfeldi and O. erosus supports the latter belonging to the genus Ips as proposed by Wood (1982) and Escherich (1923), However, more genetic markers and more species of the genera Orthotomicus and Pityokteines have to be analysed to resolve the phylogenetic positions of I. sexden tatus and I. mannsfeldi within the tribe Ipini.