Image 1 below shows a Prosotas sp. from Tat Mok, nc Thailand. It looks sufficiently different to the usual P. nora encountered in Thailand that I think this should be P. pia.
I have read a similar thread on butterfly circle where ID of pia was discussed
http://www.butterflycircle.com/showt...t-in-Singapore
Several things I specifically note about this image are the white, upper edge of the outermost discal band (both upperwing and underwing), is notably less jagged than seen in nora in Thailand. and the general colouration is much greyer than I have seen in nora in Thailand that always seem to have a distinct buff or brown cast.
I also attach (images 2 and 3) a couple of typical P. nora from e. Thailand for comparison.
Image 1. P. pia? Tat Mok.
IMG_1035.JPG
Image 2. P. nora Khao Soi Dao
b4830 Common Lineblue (Prosotas nora ardates) - Khao Soi Dao 02.JPG
Image 3. P. nora Khao Soi Dao
b4830 Common Lineblue (Prosotas nora ardates) - Khao Soi Dao 01.JPG