With Ohbayashi's key, it shoud be Capnolymma laotica Gressitt & Rondon, 1970 (elytra brown to reddish brown with pale buff pubescence forming more or less mottled arrangements, patches or bands; third antennal segment distinctly longer than fourth), like this one; it seems new for Singapore.
Thanks a lot for the identification. I checked with the description in Gressitt & Rondon and found no structural variation. It is also found in Thailand and Burma according to Ohbayashi.