ahhhhh, one of my fave insects in Hong Kong....the tortoise beetle.
One of the most distinctive features of the tortoise beetles is their domed carapace that looks much like a turtle’s upper shell. The beetle’s carapace is a combination of the elytra (hard hindwings) and the pronotum (plate over the thorax).
These are tough to photograph as they are so small and highly reflective. Interestingly, I have seen these chaps change colour...changing from shiny to matte, or from one color to another in a matter of seconds. The color-changing properties appear to be due to the movement of fluid within the cuticle. These ones did not, but next time you see one, move your shadow over it, and see if it changes.
As you can see, their shell ends in a lattice like edge, like a dragonfly wing. They can fix this to a leaf or stem and create a sticky like vacuum, making them unavailable to predators who cannot prise them loose.
There is quite a bit of colour variation in the beetles i have seen.... with some other tortoise beetles solidly and vividly colored with combinations of spots, stripes, and metallic hues.