Naming one of the world's rarest chelonians, the southern Batagur

Abstract

Using mtDNA sequences of historical museum specimens, including the herein designated lectotype of Tetraonyx affinis Cantor 1847 and topotypic specimens of Trionyx (Tetraonyx) cuvieri Gray 1831 and Tetronyx longicollis Lesson 1834, we demonstrate that the name Batagur affinis (Cantor 1847) has to be used for a recently identified critically endangered terrapin species from Southeast Asia. Further, we provide evidence that Batagur baska (Gray 1830) historically was distributed from north-easternmost India and Bangladesh to at least the Ayeyarwady and Bago estuaries in Myanmar while B. affinis occurs in the southern Malay Peninsula and Sumatra. The taxonomic allocation of the extant and extirpated Batagur populations in the northern Malay Peninsula, Cambodia and southern Vietnam remains unclear. A museum specimen from the mid-19 th century suggests that B. baska once also occurred in the Indus Delta of southern Pakistan.