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 21. Centropyxis spinosa Cash, 1905 Material examined : Mi-137, 5 ex. , Vellar estuary, 20.vii.2014 . Diagnosis : Test brown, more or less circular, dorsal side flat, furnished with variable number of spines irregularly distributed; aperture eccentric and circular; test with quartz crystals; shell 90-102 µm in diameter. Distribution in India : Andhra Pradesh , Arunachal Pradesh , Chandigarh , Himachal Pradesh , Manipur , Meghalaya , Mizoram , Nagaland , Sikkim , Tamil Nadu (present record), West Bengal .