On the basis of recent research, the now endemic Bornean Banded Pitta (Pitta schwaneri) has been taxonomically separated as a distinct species from the Malayan Banded Pitta (P. irena) and the Javan Banded Pitta (P. guajana). The birds differ significantly and consistently in the plumage of both males and females as well as in their habitat preferences.
This is yet another example in a recent trend in splitting island endemics, with a similar story following the Sunda Clouded Leopard (Neofelis diardi) and the Bornean Pygmy Elephant (Elephas maximus borneensis), both closely related to mainland species. Exactly where to draw the line will always be a matter of subjective debate among taxonomists, but as more evidence, particularly DNA sequencing, becomes available for comparative analysis, it is likely that we will see many more species separated as distinct.
Rheindt, F. E. & Eaton, J. A. 2010. “Biological species limits in the Banded Pitta Pitta guajana“. Forktail 26:86-91.