
Black-winged Stilt with black head and eye patch, Wilpaththu, Sri Lanka
The world of stilts is a confusing one. Scientists don't entirely agree on what are sub species and what are races. Usually, the geographic range helps narrow it down. In this case, based on location, it has to be the Black-winged stilt, as it is the only large stilt documented to occur in Sri Lanka (according to my book).

The black-winged stilt is a widely distributed very long-legged wader in the avocet and stilt family. The scientific name "H. himantopus" was formerly applied to a single, almost cosmopolitan species. It is now normally applied to the form that is widespread in Eurosiberia and Africa and which was formerly regarded as the nominate subspecies of "Himantopus himantopus" "sensu lato".