Complete mitochondrial genome of the fish leech Zeylanicobdella arugamensis

The complete mitochondrial genome of the fish leech Zeylanicobdella arugamensis from China has been determined for the first time in this study. It was 16,161 bp in length and consisted of 22 tRNA genes, two rRNA genes, 13 protein-coding genes (PCGs), and one control region. The nucleotide base content of Z. arugamensis mitogenome was 35.5% A, 10.4% C, 10.4% G, and 43.7% T. Start codon ATG was used in PCGs, while most of the termination codons are incomplete T or TA. The tRNA genes were ranged from 59 bp (tRNA-Arg and tRNA-Glu) to 69 bp (tRNA-Gln and tRNA-Cys) in length. The phylogenetic tree was constructed and suggested that Z. arugamensis has closer relationship to the Poecilobdella manillensis, Erpobdella octoculata, Hirudo hipponia, Whitmania acranulata, Whitmania pigra, Whitmania Laevis, Hirudo verbaba, and Hirudo medicinalis, and that they constitute a sister group.