Complete mitochondrial genome of Parastichopus californicus (Aspidochirotida: Stichopodidae).  In this study, we first determined and described the complete mitogenome sequence of Parastichopus californicus, which was 16 727 bp in length. The mitochondrial genome had the canonical mitochondrial gene content, including 13 protein-coding genes, 2 rRNA genes and 22 tRNA genes. The overall base composition of the heavy-strand was 31.5% A, 18 % G, 20.6% C and 29.9% T, with a high A + T content of 61.4%. ML phylogenetic tree indicated that P. californicus and P. nigripunctatus were clustered in one branch belonging to the genus Parastichopus. This conclusion was identical to the former result by the methods of morphological taxonomy.