Aarti ji I am sure you recollect the size of flower of this plant (D.
spathacea, Samudrashingi) to be 20 cm or 4 to 5 times bigger than D.
falcata, Medshingi. The habitat in wild is coastal swamps in south
Maharashtra, Goa and Karnataka. It is interesting that such a rare
tree is 'planted' in Mumbai. You gave all necessary details to
distinguish this plant from D. falcata except the size of flower. Hope
your confusion is now sorted out. You seem to be encountering some
unusual plants hence this difficulty. Regards, Shrikant