“…relationship and therefore have become more popular in recent years (Fan, Hu, Wen, & Zhang, 2011;Shen, Ma, Ren, & Zhao, 2009;Shen et al, 2017). Up to now, the complete mitochondrial genomes have been reported in many marine organisms, such as sea cucumber (Fan et al, 2011;Perseke et al, 2010;Scouras, Beckenbach, Arndt, & Smith, 2004;Sun, Qi, & Kong, 2010), sea urchin (Cantatore, Roberti, Rainaldi, Gadaleta, & Saccone, 1989;De Giorgi, Martiradonna, Lanave, & Saccone, 1996;Qureshi & Jacobs, 1993), brittle star (Perseke et al, 2008(Perseke et al, , 2010Scouras et al, 2004;Smith, Arndt, Gorski, & Fajber, 1993), sea lily (Perseke et al, 2008;Scouras & Smith, 2006), shellfish (Plazzi, Ribani, & Passamonti, 2013;Ren, Liu, Jiang, Guo, & Liu, 2010), and crab (Liu & Cui, 2010;Yang & Yang, 2008).…”