The complete mitochondrial genome of Parasesarma pictum (Brachyura: Grapsoidea: Sesarmidae) and comparison with other Brachyuran crabs.

Mitochondrial DNA (mtDNA) is an extrachromosomal genome which can provide important information for evolution and phylogenetic analysis. In this study, we assembled a complete mitogenome of a crab Parasesarma pictum (Brachyura: Grapsoidea: Sesarmidae) from next generation sequencing reads at the first time. P. pictum is a mudflat crab, belonging to the Sesarmidae family (subfamily Sesarminae), which is perched on East Asia. The 15,716 bp mitogenome covers 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and one control region (CR). The control region spanns 420 bp. The genome composition was highly A+T biased 75.60% and showed negative AT-skew (-0.03) and negative GC-skew (-0.47). Compared with the ancestor of Brachyura, the gene order of Sesarmidae has several differences and the gene order of P. pictum is typical for mitogenomes of Sesarmidae. Phylogenetic tree based on nucleotide sequences of mitochondrial 13 PCGs using BI and ML determined that P. pictum has a sister group relationship with Parasesarma tripectinis and belongs to Sesarmidae.