Phylogeny of Ips DeGeer species (Coleoptera : Scolytidae) inferred from mitochondrial cytochrome oxidase I DNA sequence

We used 766 bp of DNA sequence data from the mitochondrial cytochrome oxida se I gene to reconstruct a phylogeny for 39 of 43 Ips species, many of whic h are economically important bark beetles. The phylogeny was reconstructed using equally weighted and weighted parsimony. In both analyses, peripheral clades were well supported while internal clades were poorly supported. Ph ylogenetic analysis of translated amino acids produced a poorly resolved tr ee that was discordant with trees reconstructed with nucleotide sequence da ta. Two main conclusions are drawn about the monophyly of Ips and tradition al systematic groups within Ips. First, Ips is monophyletic only when I. ma nnsfeldi, I nobilis, and the concinnus and latidens species groups are excl uded. The latidens group, I. mannsfeldi, and I. nobilis form a monophyletic group with 3 Orthotomicus species, while the concinnus group has a more ba sal position. Second, the majority of the species groups in the current cla ssification for Ips are not monophyletic. European Ips species do not form a monophyletic group, contrary to common usage, and are dispersed on the ph ylogenetic tree among North American species. These results indicate that a formal systematic revision of Ips is needed. (C) 2000 Academic Press.