The Purple Sapphire
Why is it called the purple sapphire when its yellow? Often seen in grasslands and on the leaves of hedges and shrubbery. They are very shy and flighty, but can be seen sunbathing, wings open or closed, and has a short hopping flight to the flowers it loves.
The underside of the wings seen here above, are bright yellow, which is how you normally see them.
This in contrast to the sapphire blue colouration of their wings in flight, or occasionally you might be lucky enough to see one open its wings, like in this picture. Males have a purplish blue patch on the dorsal side of the forewing while the females do not.
See them at Hong Kong wetland park. http://www.wetlandpark.gov.hk/