Molecular phylogeny reconstruction and biogeographic pattern of Rays (Elasmobranchii: Myliobatiformes) from Indian coastal waters

Abstract

In the present study, the phylogenetic relationship among Myliobatiformes was reconstructed from the Indian waters based on the cytochrome c oxidase subunit I (COXI) gene. Overall, 307 sequences (18 collected from Mandapam fish landing centres, Tamil Nadu, and 289 from the previous literatures) from 34 species of Myliobatiformes were clustered under two major phylogenetic clades. The families Mobulidae, Rhinopteridae, Plesiobatidae, and Gymuridae were monophyletic, while the families Myliobatidae and Dasyatidae were polyphyletic. Further, the genera Aetomylaeus (Myliobatidae) and Pateobatis (Dasyatidae) show polyphyly by showing deep genetic divergence in the phylogenetic tree. Based on the phylogenetic tree analysis, Himanutra uarnak appears to be H. tutul in the Indian waters. Similarly, Neotrygon indica should be consistently used instead of N. kuhlii, as Indian specimens forms a distinct subclade within N. kuhlii species complex. In this study, it is also observed that several entries in the NCBI GenBank are erroneous; thus, an updation of data is recommended based on the present study. The biogeographic patterns revealed H. tutul, Maculabatis gerrardi, Brevitrygon imbricata, and Gymnura poecilura from the Indian coast form a separate haplotype compared to other geographical areas (Indo-west Pacific). In addition, G. poecilura and B. imbricata were genetically divergent between east and west coast populations of India, indicating a possibility of cryptic species.