Structure of Chinese Daphnia pulex mitochondrial genome. COI, COII, COIII refer to the cytochrome oxidase subunits, Cytb refers to cytochrome b, ND1 - ND6 refer to NADH dehydrogenase components, and rrL and rrnS refer to rRNAs. tRNA genes are denoted by one letter symbol according to the IPUC-IUB single-letter amino acid codes. L1, L2, S1 and S2 denote tRNALeu(CUN), tRNALeu(UUR), tRNASer(AGN) and tRNASer(UCN), respectively. D-loop indicates A+T-rich region. Gene names outside the ring are coded on the majority strand while those inside are on the minority strand.