Characterization and phylogenetic position of two sympatric sister species of toxic flatwormsPlanocera multitentaculataandPlanocera reticulata(Platyhelminthes: Acotylea)

The complete mitochondrial genomes of two toxic flatworm species of the genusPlanocerawere determined. The total length of mitochondrial DNA (mtDNA) was 15,657 bp inPlanocera multitentaculataand 15,486 bp inPlanocera reticulataand included 12 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 4 non-coding regions. The mitochondrial gene arrangement of these planocerid species was identical to that of previously described acotylean species,Hoploplana elisabelloi, and also to those of other polyclads. Maximum likelihood analysis against 14 Platyhelminthes showed that a tree was robustly constructed using 12 protein-coding genes than COI gene.