The complete mitochondrial genome of Neobenedenia melleni (Platyhelminthes: Monogenea): mitochondrial gene content, arrangement and composition compared with two Benedenia species

The complete mitochondrial (mt) genome sequences of Neobenedenia melleni were determined and compared with those of Benedenia seriolae and B. hoshinai. This circular genome comprises 13,270 bp and includes all 36 typical mt genes found in flatworms. Total AT content of N. melleni is 75.9 %. ATG is the most common start codon, while nad4L is initiated by GTG. All protein-coding genes are predicted to terminate with TAG and TAA. N. melleni has the trnR with a TCG anticodon, which is the same to B. seriolae but different from B. hoshinai (ACG). The mt gene arrangement of N. melleni is similar to that of B. seriolae and B. hoshinai with the exception of three translocations (trnF, trnT and trnG). The overlapped region between nad4L and nad4 was found in the N. melleni mt genome, which was also reported for the published Gyrodactylus species, but it was not found in those of B. seriolae and B. hoshinai, which are non-coding regions instead. The present study provides useful molecular characters for species or strain identification and systematic studies of this parasite.