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 33. Difflugia lebes Penard, 1899 Material examined : Mi-131, 2 ex. , Karaikkal estuary, 06.i.2013 . Diagnosis : Test light brown in colour; semi-circular test; aperture large and covers entire edge of the test; test covered with siliceous particles; collar straight; more number of nuclei; test dimension 150-190µm. Distribution in India : Andhra Pradesh , Tamil Nadu (present record).