This was photographed about 12 months ago in rain forest at Gunung Mulu National Park in Sarawak. I was able to identify another shield bug seen nearby but can't make any headway with this one, apart from a single photo found on the web that suggested it was a Pentatomidae sp. Any thoughts greatly appreciated.
These are squashbugs (members of the family Coreidae). I suspect they're nymphs (although there's a chance they're adults of a short-winged species) so that may make them even harder to ID any further than that.
Thanks for this suggestion of family Coreidae. Working from it, I found a few photos of Prionolomia gigas, which is remarkably similar in shape and patterning, but appears to have been taken in Yunnan. Not sure if the distribution extends to Borneo.