Phylogeny and taxonomy of endangered South and South-east Asian freshwater turtles elucidated by mtDNA sequence variation (Testudines: Geoemydidae: Batagur, Callagur, Hardella, Kachuga, 36 ,[429][430][431][432][433][434][435][436][437][438][439][440][441][442] Using DNA sequences of the mitochondrial cytochrome b gene, we investigated phylogeny and taxonomy of South and South-east Asian turtles of all species and subspecies of the genera Batagur, Callagur, Hardella, Kachuga and Pangshura. We found three major clades: (i) a moderately to well-supported clade containing all large riverine species assigned so far to Batagur, Callagur and Kachuga ; (ii) a well-supported monophylum comprising the four Pangshura species; and (iii) Hardella that could constitute either the sister-taxon of Pangshura or of a clade comprising Batagur, Callagur, Kachuga and Pangshura. The genus Kachuga is clearly polyphyletic. Therefore, we recommend placing all Batagur, Callagur and Kachuga species in one genus. According to the International Code of Zoological Nomenclature Batagur Gray, 1856, being originally erected at higher rank, takes precedence over the simultaneously published name Kachuga Gray, 1856, and the younger name Callagur Gray, 1870, resulting in an expanded genus Batagur. Indonesian and Malaysian Batagur baska proved to be highly distinct from our sequences of this species from the Sundarbans (Bangladesh, adjacent India), suggesting that a previously unidentified species is involved. This finding is of high conservation relevance in the critically endangered B. baska. The currently recognized subspecies within Hardella thurjii , Pangshura smithii and P. tentoria do not correspond well with mtDNA clades. Considering that the two subspecies of H. thurjii are likely to be based only on individual ontogenetic differences, we propose abandoning the usage of subspecies within H. thurjii . In the Ghaghra River, Uttar Pradesh (India) we detected shared haplotypes in P. smithii and P. tentoria, implying that the unusual morphological characters of the Ghaghra River population of P. tentoria could be the result of interspecific hybridization. Peter Praschag, Am Katzelbach 98, A-8054 Graz, Austria.