The full mitochondrial genome sequence of the greater argonaut Argonauta argo (Cephalopoda, Argonautoidea) and its phylogenetic position in Octopodiformes

Abstract

The greater argonaut Argonauta argo is a species of the paper nautilus (Argonautidae), which is a family in Octopoda. In this paper, we report its full mitogenome sequence, which was obtained from a specimen collected in the Japan Seas near Oki Island, Shimane Prefecture, in Japan. The sequence was determined using the NGS Illumina HiSeq platform. With its 37 genes, the mitogenome shows a typical metazoan and Octopoda genomic structure, and similar to the mitogenome of the previously reported congener, A. hians. To confirm A. argo phylogenetic position in Octopoda, we conducted maximum likelihood phylogenetic analysis, using a data set including publicly available 17 Octopodiformes, five Decapodiformes, three Nautiloids and two outgroup Conchiferans. The result confirmed the affinity of Argonautidae to Tremoctopus, and the sister group position of this clade against the rest of incirrate Octopods. The mitogenome and phylogeny of A. argo reported here will be useful for future studies involving this enigmatic species, including on the reacquisition of external calcified shell structures in mollusks.

Keywords:

• Paper nautilus
• shelled octopods
• mitogenome
• Oki Island
• Sea of Japan

Acknowledgments

The authors would like to thank Masaki Yamamoto (National Institute of Technology (KOSEN), Wakayama College), Takenori Sasaki and Nagisa Nakaji (The University Museum, The University of Tokyo) for their assistance on sampling, molecular experiments, and data-set building for the phylogenetic analyses in this study. Genome sequencing was done with the support of the Platform for Advanced Genome Science (PAGS) Project.

Disclosure statement

The authors declare that there is no conflict of interest. All authors are responsible for the content and writing of the paper.

Data availability statement

The full mitochondrial genome sequence reported in this study is registered in and openly available from the National Center for Biotechnology Information (NCBI) Genbank database (Accession No.: LC596061; https://www.ncbi.nlm.nih.gov/nuccore/LC596061.1).

The shell (eggcase) of the specimen was deposited at The University Museum of The University of Tokyo, Japan (Takenori Sasaki; [email protected]) under the voucher number UMUT-RM33391.

Additional information

Funding

This study was supported by the FY2016 Research Grant for Chemistry and Life Sciences (The Asahi Glass Foundation), the FY2017 Research Grant for Zoology (Fujiwara Natural History Research Foundation) (both awarded to DHES), and the FY2018 Grant-in-Aid for Scientific Research (C) [Grant number: 18K06363] awarded to MAY and DHES. This work was also supported by JSPS KAKENHI [Grant Number 16H06279] for PAGS to TI, AT, and MAY.