The early instar of the Plain Nawab caterpillar unlike that of the later instar, has black color head (instead of green) and green body without any patterns.
As I was about to move on, I noticed one of the caterpillars has a slight reddish horns.
Interesting ! Again without thinking I took a few more shots and continued my journey up the steps along the Marang Trail.
Last night, when I was sorting through my photos, deciding which to delete and which to keep, I noticed there is something different about the 'red-head' Plain Nawab caterpillar from Mt Faber.
It is NOT a Plain Nawab caterpillar! It is the caterpillar of the Blue Nawab (Polyura schreiber).
So what is the big deal you ask? First, the Blue Nawab caterpillar is uncommon. More important is the fact that this one is found feeding on Saga (Adenanthera pavonina) instead of its normal food plant - Rambutan (Nephelium lappaceum). This validates BIG's 2001 finding that Adenanthera pavonina is an alternative host plant for Blue Nawab.
Three cheers for BIG !!