Nuculid bivalves from Surma Group, Mizoram, India

Abstract

The records of nuculid bivalves from the Surma Group sediments of Mizoram, India, are very rare. This paper describes 3 known and 4 new forms of bivalves of the family nuculidae which were collected in the course of field study from Upper Bhuban Formation of Bhuban Subgroup (Surma Group), Mizoram. They are : Nucula alcocki Noetling, Nucula warsarensis Eames, Nucula cf. pulchara Hinds, Nucula agrawali n.sp., Nucula sahnii n.sp., Nucula tewarii n.sp., and Acila (Truncacila) kachharai n.sp. The first three forms, though, known from the other areas of the Indian subcontinent, are reported for the first time from the study area and their synonymy is updated.

These forms, together with the other associated vivalves, gastropods and decapod crustacea, indicate a Lower Miocene (Aquitanian-Burdigalian) age and shallow marine enviroment of deposition for the Upper Bhuban Formation.