ZHONG, M.*; HALANYCH, K. M. ; Auburn University; Auburn University: Mitochondrial Genomes of Three Terebelliformia Annelids

Sequencing of complete mitochondrial genomes has become a useful tool for inferring animal phylogeny. Complete mitochondrial DNA (mtDNA) sequences have been determined for many invertebrate species and partial sequences for hundreds of others. Since the rate of gene arrangement of mtDNA varies among different lineages, gene order may provide resolution at differing taxonomic levels. To further understand the phylogenetic potential of complete mitochondrial genome sequence data in Annelida (segmented worms), we obtained mitochondrial genome data for three Terebelliformia worms (Eclysippe vanelli–Ampharetidae, Pista cristata–Terebellidae and Terebellides californica–Trichobranchidae) and combined these with available GenBank data. The goal of this work is to elucidate phylogenetic relationships among the 5 recognized families within Terebellidormia: Alvinellidae, Ampharetidae, Pectinariidae, Terebellidae and Trichobranchidae. Sequence results show similar gene arrangement in these three taxa to annelid genomes reported previously, suggesting the gene order is conserved across Annelida. Thus, gene trees, rather than gene order, is being used to determine Terebelliformia relationships.