The complete mitochondrial genome of the hermit crab Diogenes Edwardsii (Anomura: Diogenidae) and phylogenetic relationships within infraorder Anomura

Abstract

Abstract Complete mitochondrial genome (mitogenome) can provide important information for gene rearrangement, molecular evolution and phylogenetic analysis. Currently, only a few mitogenomes of Paguridae in the infraorder Anomura have been reported. This study reports the first complete mitogenome of the hermit crab Diogenes Edwardsii assembled using high-throughput sequencing. The mitogenome of D. Edwardsii is 19,858 bp in length and comprises 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes. There are 28 and 6 genes observed on the heavy and light strands, respectively. The genome composition was highly A + T biased (72.16%), and exhibited a negative AT-skew (-0.110) and positive GC-skew (0.233). The D. Edwardsii mitogenome possessed distinctive gene arrangements compared with the reported mitogenomes of the species in the same family. Phylogenetic analyses based on the nucleotide dataset of 16 Anomura species indicated that D. Edwardsii was closely related to Clibanarius infraspinatus. Positive selection analysis showed that two residues located in cox1 and cox2 were identified as positively selected sites with high BEB value (> 95%), indicating that these two genes are under positive selection pressure. This finding helps to better understand the gene rearrangements and the evolutionary status of D. Edwardsii, and provide data for further phylogenetic study of Anomura.