Characterization and phylogenetic analysis of the complete mitochondrial genome of Aipysurus eydouxii Gray 1849 (Elapidae: Hydrophiinae)

Abstract

Hydrophiine sea snakes represent ecologically significant and species-rich marine predatory reptiles, many of which inhabit marine environments throughout their entire lifecycles. However, due to morphological variability and limited molecular phylogenetic studies, the taxonomic relationships within this group remain unclear. In this study, we present the first complete mitochondrial genome of Aipysurus sea snakes, specifically Aipysurus eydouxii Gray 1849. The mitogenome comprises 17,228 base pairs and contains a total of 37 genes , plus a putative control region. This study provides valuable genetic data that will contribute to the future taxonomic classification and ecological protection of hydrophiine sea snakes.

Keywords: Aipysurus eydouxii; Hydrophiinae; Mitochondrial genome.

Figure 1.

Photograph of morphology features of the marbled sea snake Aipysurus eydouxii Gray 1849. The photos of Aipysurus eydouxii were taken at Marine Biological Museum, Guangxi Institute of Oceanology, Beihai, China (photographed by Shengping Zhong). The species was identified using scalation and color pattern as the classic characteristics.

Figure 2.

Gene map of the complete mitochondrial genome of A. eydouxii. The complete mitochondrial genome of A. eydouxii contains a total of 37 genes including 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes.

Figure 3.

Phylogenetic tree of 13 species in Elapidae. The complete mitogenomes were downloaded from GenBank and the following sequences were used Laticauda colubrina NC_036054 (Kim et al. 2018), L. laticaudata NC_036053 (Kim et al. 2018), L. semifasciata NC_036055 (Kim et al. 2018), Emydocephalus ijimae MK775531 (Yi et al. 2019), Hydrophis platurus MK775530 (Yi et al. 2019), H. melanocephalus MK775532 (Yi et al. 2019), H. curtus NC_046794 (Qiu et al. 2019), H. cyanocinctus NC_046795 (Qiu et al. 2019), H. ornatus NC_066233 (Xiaokaiti et al. 2022), Naja atra NC_011389 (unpublished), N. naja NC_010225 (Yan et al. 2008), Notechis scutatus GCA_900518725 (unpublished), and Ophiophagus hannah NC_011394 (Chen and Lai 2010). The phylogenic tree based on the concatenated nucleotide sequences of 13 mitochondrial PCGs was constructed by maximum-likelihood method via PhyML online server (http://www.atgc-montpellier.fr/phyml/), using GTR substitution model with 1000 bootstrap replicates. The bootstrap values are indicated at each branch nodes; terrestrial elapids were rooted to be outgroup species.