Studies on the free-living protozoan fauna of estuaries in the coastal zone of Tamil Nadu, India Author Bindu, L. text Records of the Zoological Survey of India 2021 121 1 61 75 journal article 10.26515/rzsi/v121/i1/2021/141506 2581-8686 13186453 26. Difflugia acuminata Ehrenberg, 1838 Material examined : Mi-281, 5 ex. , Vellar estuary, 20.vi.2013 . Diagnosis : Shell light brown, cylindrical, slightly tapering towards the apertural end; posterior end pointed or with a hollow and open tube or spine; shell composed of mineral particles. Distribution in India : Assam , Andhra Pradesh , Kerala (Nilgiri Biosphere Reserve), Meghalaya, Rajasthan, Tamil Nadu, Tripura, West Bengal .