The Historical Speciation of Mauremys Sensu Lato: Ancestral Area Reconstruction and Interspecific Gene Flow Level Assessment Provide New Insights

Abstract

Mauremys sensu lato was divided into Mauremys, Chinemys, Ocadia, and Annamemys based on earlier research on morphology. Phylogenetic research on this group has been controversial because of disagreements regarding taxonomy, and the historical speciation is still poorly understood. In this study, 32 individuals of eight species that are widely distributed in Eurasia were collected. The complete mitochondrial (mt) sequences of 14 individuals of eight species were sequenced. Phylogenetic relationships, interspecific divergence times, and ancestral area reconstructions were explored using mt genome data (10,854 bp). Subsequent interspecific gene flow level assessment was performed using five unlinked polymorphic microsatellite loci. The Bayesian and maximum likelihood analyses revealed a paraphyletic relationship among four old genera (Mauremys, Annamemys, Chinemys, and Ocadia) and suggested the four old genera should be merged into the genus (Mauremys). Ancestral area reconstruction and divergence time estimation suggested Southeast Asia may be the area of origin for the common ancestral species of this genus and genetic drift may have played a decisive role in species divergence due to the isolated event of a glacial age. However, M. japonica may have been speciated due to the creation of the island of Japan. The detection of extensive gene flow suggested no vicariance occurred between Asia and Southeast Asia. Inconsistent results between gene flow assessment and phylogenetic analysis revealed the hybrid origin of M. mutica (Southeast Asian). Here ancestral area reconstruction and interspecific gene flow level assessment were first used to explore species origins and evolution of Mauremys sensu lato, which provided new insights on this genus.

The complete mitochondrial genome of the Cyclemys fusca (Chelonia: Geoemydidae)

“…As shown in the phylogenetic tree (Figure 1), C. fusca and five species of genus Cyclemys, formed a monophyletic group, and the genus Cyclemys is closely related to genus Notochelys, Heosemys, and Sacalia. This conclusion is consistent with previously reported results (Wang et al 2012(Wang et al , 2017Zhou et al 2015).…”

The complete mitochondrial genome of the Heosemys depressa (Testudines, Geoemydidae)

“…The Arakan forest turtle (Heosemys depressa), which is critically endangered, is endemic to Myanmar and belongs to the genus Heosemys within the family Geoemydidae (Rahman et al 2015 (Zhou et al 2015), and the complete mtDNA of H. depressa was amplified and sequenced using 15 primer pairs. The complete mitochondrial genome sequence of H. depressa is 16,773bp in length (GenBank accession No.…”

The complete mitochondrial genome of the endangered Assam Roofed Turtle, Pangshura sylhetensis (Testudines: Geoemydidae): Genomic features and phylogeny

“…Finally, for each of the two datasets, the sequences of all PCGs were concatenated using SequenceMatrix v1.7.84537 [45]. As NADH dehydrogenase subunit 6 (nad6) is encoded on the light-strand [46][47][48], the reverse complement of nad6 sequences along with other PCGs were used for phylogenetic tree construction. The suitable models for phylogenetic analyses were estimated by partitioning of each gene using PartitionFinder 2 [49] at the CIPRES Science Gateway V. 3.3 [50] (S2 Table).…”