The First Record of <i>Ocypode sinensis</i> (Decapoda: Ocypodidae) from the Korean Peninsula: How the Complete Mitochondrial Genome Elucidates the Divergence History of Ghost Crabs

Abstract

Ghost crabs, as a species of the Ocypode within the subfamily Ocypodinae, are distributed in the upper intertidal zone worldwide and are ecologically remarkable. They play an important role in the energy circulation in the intertidal zone and are used as an ecological indicator to predict the impacts of environmental change or anthropogenic activities on the marine ecosystem. In this study, we provide the first evidence for the distribution of O. sinensis in Jeju Island and the southern coastal area on the Korean Peninsula. We generated a high-fidelity mitochondrial genome (mitogenome) for the species. The mitogenome was assembled into a circular chromosome of 15,589 bp, including 13 protein-coding genes, two ribosomal RNA genes, and twenty-two transfer RNA genes. High genetic variation compared with closely related species enabled the precise reconstruction of phylogenetic relationships and an estimation of the divergence times among the Ocypode species. The phylogenetic inference indicated that O. sinensis forms a monophyletic clade with O. cordimanus and diverged from ancestral species approximately 20.41 million years ago.

Keywords

• unrecorded species
• morphology
• mitogenome
• phylogeny
• fossil data