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 12. Centropyxis cassis Deflandre, 1929 Material examined : Mi-338, 6 ex. , Kaliveli estuary, 06.i.2013 ; Mi-450, 6 ex. , Vellar estuary, 08.i.2013 . Diagnosis : Test elliptical, yellowish brown in colour, test formed of quartz particles; fundus rounded; flanks less arched; oral aperture semi circular and surrounded by large pebbles; test diameter 90-99 µm. Distribution in India : Assam , Andhra Pradesh , Meghalaya , Odisha , Tamil Nadu (present record), Uttarakhand , West Bengal .