This is likely to be Amathusia friderici.
The HW 4th dark band is strongly notched by the veins.
http://beyondnostalgia.livedoor.blog...s/8820190.html

Amathusia phidippus have this band entire & un-notched.
https://m.singapore.biodiversity.onl...doptera-000251

All other species have some degreeof notchings.
Some can IDed by other features.

eg A. perakana have the 4th band partially broken into separate spot & the FW is sharp.
https://farm1.staticflickr.com/618/2...ac383a60_b.jpg
A. masina is reddish & have the FW postdiscal band solid brown without the whitish colour break seen in all other species.
http://www.samuibutterflies.com/02_i...namalaya.v.jpg

The hostplant is the widely cultivated oil-palm & the butterfly is said to be common in some places.
Form utana which is very dark was formerly thought to be a separate species.


TL Seow: Cheers.