This is exactly Veneridae Fam. (possible Gen. Pitar or Lamelliconcha with a lot of representatives in the Indian Ocean) in total more than 400 species. Should call Claudio Galli - try [email protected]
Thank you Henk, for confirming it, as I had too identified it as Clementia papyracea. As I haven't done benthos identification before, I was not much confident to say it. Yes as you said it has a very thin shell, quite transparent and whitish colouration.