Dear Surajit Ji, Sorry for my delayed response!
Firstly thanks for sending me the literature of Bengal plants. I think your doubts are genuine. May I request you to check (if possible) the nuts of the plant? If they are biconvex, it would be P. pulchra (Blume) Sojak, if trigonus, P. stagnina should be correct. Regards, Ritesh. --
