Resolving phylogeny at the family level by mitochondrial cytochrome oxidase sequences: Phylogeny of carrion beetles (Coleoptera, Silphidae)

We investigated the phylogenetic relationships of carrion beetles (Coleopte ra, Silphidae) using 2094 bp of their mitochondrial cytochrome oxidase subu nit I and II and tRNA leucine gene sequences. Shorter fragments of this gen e region previously have been used to establish generic relationships in in sects. In this study, they provided more than sufficient resolution, althou gh the third positions of the protein-coding sequences reached saturation f or the deeper divergences. This first published phylogeny for the Silphidae comprises 23 species from 13 genera sampled across the geographic range of the family. In addition, we included species from three related families a s outgroups. One of these families, the Agyrtidae, was, until recently, inc luded in the Silphidae, but its resolution here justifies its current posit ion as a separate family. The silphid subfamilies Nicrophorinae and Silphin ae are monophyletic in all analyses. All genera for which several species w ere sampled are supported as monophyletic groups, with the exception of the genus Silpha. European and North American representatives of two Nicrophor us species described from both continents are supported as each others' clo sest relatives. The lineage that colonized Gondwanaland and that most likel y originated in the Palearctic is the most basal within the Silphinae. (C) 2000 Academic Press.