We investigated relationships among Asian fl apshell turtles by using 2286 bp of mitochondrial DNA for phylogenetic reconstructions and relaxed molecular clock calculations. Currently three taxa are recognized, the unspotted species Lissemys scutata and L. punctata, with the unspotted subspecies L. p. punctata and the spotted subspecies L. p. andersoni. However, we found fi ve deeply divergent clades, two of which correspond to L. scutata (Myanmar; perhaps also adjacent Thailand and Yunnan, China) and L. p. andersoni (Indus, Ganges and Brahmaputra drainages; western Myanmar), respectively. Within L. p. punctata from peninsular India and Sri Lanka three distinct clades were identifi ed, two from peninsular India and one from Sri Lanka. The two clades from peninsular India are more closely related to L. p. andersoni than to fl apshell turtles from Sri Lanka. Due to a genetic divergence resembling L. scutata, we propose to separate Sri Lankan populations as the distinct species L. ceylonensis (Gray, 1856) from L. punctata. Furthermore, we suggest to restrict the name L. p. punctata (Lacepède, 1788) = L. p. punctata (Bonnaterre, 1789) to populations from southern peninsular India, whereas the name L. p. vittata (Peters, 1854) should be applied to unspotted fl apshell turtles from northern peninsular India. We classify all three taxa from the Indian subcontinent as subspecies because (1) there is morphological and genetic evidence that L. p. andersoni intergrades with L. p. vittata, and (2) the genetic divergence among L. p. punctata, L. p. andersoni and L. p. vittata resembles the degree of differentiation as observed between the latter two subspecies, whereas the differences between L. ceylonensis and L. scutata and among these species and the subspecies of L. punctata are about twice the values as observed among the subspecies of L. punctata. The formation of the subspecies of L. punctata was dated to have occurred between the uppermost Miocene and the Early Pleistocene (mean split ages of approx. 4.5 and 4.2 million years); the origin of L. ceylonensis and L. scutata, to a range between the Early Miocene and the Lower Pliocene (mean split ages of approx. 8 and 11 million years, respectively).
Based on 2354 bp of mitochondrial DNA (12S rRNA, ND4, cyt b) and 2573 bp of nuclear DNA (C-mos, ODC, R35), we re-examine the phylogenetic relationships of Nilssonia species. Individual and combined analyses of mitochondrial and nuclear DNA using Maximum Likelihood and Bayesian approaches confirm the monophyly of the genus. While mitochondrial data alone could not resolve the phylogenetic position of N. formosa, nuclear data support a sister group relationship of N. formosa and the remaining Nilssonia species. Combined analyses of mitochondrial and nuclear DNA suggest the following branching pattern, with N. formosa as the sister taxon of the remaining species: N. formosa + ((N. gangetica + N. leithii) + (N. hurum + N. nigricans)). Among the samples we studied is the first record of N. formosa for Yunnan, China, and the first record of wild-living N. nigricans for Bangladesh. In N. gangetica, each of the studied major river basins harbours a genetically distinct population, suggesting that at least three distinct management units should be distinguished: (1) Brahmaputra River; (2) Indus and Ganges Rivers plus Ganges Delta; and (3) Mahanadi River.
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