The complete mitochondrial genome of Echiniscus testudo (Heterotardigrada: Echiniscidae)

Abstract

The complete mitchondrial genome of Echiniscus testudo, a cosmopolitan heterotardigrade collected in Japan, has been sequenced using a single molecule real-time (SMRT) sequencing long read after whole genome amplification from a single individual. The genome has a total length of 15,817 bp, consisting of 13 protein-coding genes, 20 tRNA, 2 rRNA genes, and an AT-rich control region. The nucleotide composition was extremely AT-rich, with 78.41% AT. Being in a different class of the phylum Tardigrada, there is a large sequence divergence from the previously reported mitochondrial genome of the eutardigrade Ramazzottius varieornatus, but the gene order of protein-coding genes are mostly conserved. This is the first report of a complete mitochondrial genome of a heterotardigrade.

Keywords:

• Mitochondrial genome
• Echiniscus testudo
• tardigrade
• PacBio sequencing

Acknowledgments

The authors thank Nozomi Abe for technical assistance.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

This work was supported by KAKENHI Grant-in-Aid for Scientific Research (B), No. 17H03620, in part by research funds from the Yamagata Prefectural Government and Tsuruoka City, Japan.