15. My guess Hippotion echeclus male.

4 species are near identical; their IDs depend on the HW tornal pale patch & whether the base is black, as well as FW shape & intensity of the markings.
The FW of echeclus is less convex than in the other species, so that the dark line from the apex is straighter there than in the other species.
http://tpittaway.tripod.com/china/h_ech.htm
Female echeclus from Sumatra
http://sphingidae.myspecies.info/sit..._female_up.jpg
http://tpittaway.tripod.com/china/h_boe.htm
http://tpittaway.tripod.com/china/h_ros.htm
http://tpittaway.tripod.com/china/h_raf.htm

TL Seow:Cheers.