The Lutrinae (Mustelidae, Carnivora, Mammalia) from the Upper Miocene to the Lower Pleistocene deposits of Pakistan

Well-preserved new dental material of subfamily Lutrinae (Mustelidae, Carnivora) comprising of upper and lower premolars and molar were recovered from the Hasnot, Padhri, Bhimber areas of the Siwaliks of Pakistan. Three specimens are described in this study: an m1 collected from Pleistocene deposits of Bhimber is attributed to Enhydriodon cf. falconeri, an upper fourth premolar (P4) recovered from Hasnot (7 to 5.3 Ma) is so unique in having round borders/external walls, basal lingual cingulum is straight at mesial border, postparacrista short and having less buccal concavity, lack a cusplet between proto- and hypocone that it allowed us to create a species, Sivaonyx sarwari n. sp., and an isolated lower fourth premolar (p4) collected from Padhri (7-5.5 Ma) is described as Sivaonyx bathygnathus. Among these, Enhydriodon falconeri is reported for the first time from the Pleistocene deposits of the Siwaliks, while Sivaonyx sarwari n. sp. represents the smallest species of the genus. The present specimens add to the records of the rare mustelid species and also challenge the evolutionary time transgression of some Siwalik lutrine species proposed by previous studies.