Mitogenomic Phylogeny of Tonnoidea Suter, 1913 (1825) (Gastropoda: Caenogastropoda)
by
Jiawen Zheng
1,†,
Fengping Li
1,†,
Mingfu Fan
1,
Zhifeng Gu
1,
Chunsheng Liu
1, 
Aimin Wang
1 and
Yi Yang
1,2,* 
1
School of Marine Biology and Fisheries, Hainan University, Haikou 570228, China
2
Sanya Nanfan Research Institute, Hainan University, Sanya 572025, China
*
Author to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Animals 2023, 13(21), 3342; https://doi.org/10.3390/ani13213342
Submission received: 5 September 2023
/
Revised: 1 October 2023
/
Accepted: 25 October 2023
/
Published: 27 October 2023
(This article belongs to the Section Animal Genetics and Genomics)
Simple Summary
We sequenced the complete mitochondrial genomes of nine Tonnoidean species, and analyzed the genomic features including genome size, gene order, nucleotide composition and Ka/Ks ratio. The reconstructed phylogeny based on mitogenomic data supported the Tonnoidea classifications at family levels, but their internal relationships remained unclear. At the species level, the present study indicates that species diversity within Bursidae might be underestimated.
Abstract
The Tonnoidea Suter, 1913 (1825) is a moderately diverse group of large predatory gastropods, the systematics of which remain unclear. In the present study, the complete mitochondrial genomes of nine Tonnoidean species were sequenced. All newly sequenced mitogenomes contain 13 protein-coding genes (PCGs), 22 transfer RNA genes and two ribosomal RNA genes, showing similar patterns in genome size, gene order and nucleotide composition. The ratio of nonsynonymous to synonymous of PCGs indicated that NADH complex genes of Tonnoideans were experiencing a more relaxed purifying selection compared with the COX genes. The reconstructed phylogeny based on the combined amino acid sequences of 13 protein-coding genes and the nucleotide sequences of two rRNA genes supported that Ficidae Meek, 1864 (1840) is a sister to Tonnoidea. The monophylies of all Tonnoidean families were recovered and the internal phylogenetic relationships were consistent with the current classification. The phylogeny also revealed that Tutufa rebuta (Linnaeus, 1758) is composed of at least two different species, indicating that the species diversity within Bursidae Thiele, 1925 might be underestimated. The present study contributes to the understanding of the Tonnoidean systematics, and it could provide important information for the revision of Tonnoidean systematics in the future.
Keywords:
Tonnoidean; mitochondrial genome; phylogeny; species diversity
